The big Japanese akita dog is stopped in his tracks by the box on wheels, unsure whether it is an equal to be greeted or another south London surface to be marked. His owner, hot on his heels, is just as surprised when he rounds the corner.

“STOP, in the name of love!” a man sings at the machine, palm outstretched, jumping back in mock alarm. “What the hell is that?”

It is a self-driving delivery robot, and it is also a conversation starter – a unit of rounded plastic about the size of a mini-fridge, sending ripples through the streets near Borough station, where Starship Technologies has its business headquarters. The company operates a small fleet of 10-15 robots, delivering mostly takeaway food orders, and increasingly parcels, over distances of up to two miles.

The fact the machines still turn heads – and must be accompanied on journeys by handlers, as agreed by Starship with Southwark borough council – suggests the future of fully autonomous delivery is not yet here. But it is on its way, and faster than the robots’ top speed of 4mph might suggest.

With politicians and the public more wary of self-driving cars than ever following the first pedestrian fatality last month, and drone activity severely regulated, ground robots delivering small goods seem a comparatively straightforward proposition. As online shopping booms, consultants McKinsey & Co predicted in 2016 that within a decade 80% of all items would be delivered autonomously.

But with robots the future of “last-mile logistics”, there is fierce competition to be the company at the front of the pack.

There is Nuro, an autonomous vehicle promising to “run your errands for you”, for which two former principal engineers of Google’s self-driving car project received $92m (£64.6m) in funding. There is the fully electric, self-driving “e-Palette” unveiled by Toyota and Pizza Hut at the Consumer Electronics Show in Las Vegas, and Gita, Piaggio Fast Forward’s “cargo droid … big enough to carry a case of wine”.

And then there are the companies already out on the streets, among them Starship and its competitor Marble, which announced a further $10m (£7.2m) in funding last week.

Starship’s London operation is modest compared with that in many US cities, the Estonian capital of Tallinn (home of the company’s co-founder, Ahti Heinla, a founding engineer of Skype), and especially Milton Keynes, which is attempting to establish itself as a tech hub. There, Starship robots are free to operate without handlers – or “ambassadors”, as spokesman Henry Harris-Burland calls them.

“It’s like a robot playground,” he says of Milton Keynes, pointing to its pedestrian density, wide pavements and underpasses. “That, as well as the city being very welcoming.”

Recently Starship’s efforts have been focused on gauging the appetite for autonomous delivery beyond its corporate food delivery partners. Last month it launched a trial “plug and play” service in Milton Keynes to offer autonomous delivery to any business owner for a small one-off cost. And on Monday Starship announced its first major commercial deployment at the finance developer Intuit’s Silicon Valley campus, delivering food from the staff cafeteria.

Starship is making autonomous delivery available to everyone, says Harris-Burland. But the potential impact – most obviously on economies and employment – is unclear.

Fears of mass unemployment caused by advances in automation since the early 19th century have, in many cases, not been borne out. Technology only replaces people when it is more profitable for it to do so – and even then it creates more, new and often better-paying jobs. A Centre for Cities report this year found that there were 60% more jobs in most UK cities now than there were in 1911.

Harris-Burland is confident that, far from causing job losses, Starship’s operations will contribute to a net increase due to efficiency gains and industry growth, in addition to the creation of robot-specific roles.

Though its machines operate mostly autonomously, when one does detect a hazard – such as a busy road or an unnavigable obstacle – it signals a call centre in Washington DC or Tallinn. An operator then assumes control of the robot, assessing the risk through its nine or 10 cameras and either directing it manually or playing a prerecorded message to scold obstructive pedestrians – but only for as long as it takes to get the robot back on its way.

There are also handler roles, whose only power over the robot is an emergency stop button and whose primary responsibility is to answer pedestrians’ questions and report back to the company.

Harris-Burland points to jobs like these to counter concerns about automation. “If I was to have said a year ago: ‘We’ve got a robot operator job available,’ they would have said, ‘Are you mad?’” Plus, he adds, Starship robots can only have so much impact when deliveries of more than three miles are beyond their reach.

But San Francisco, where more autonomous delivery companies are operating, has already encountered problems with robots crowding their sidewalks. (Marble’s machines, notably, are about the size of filing cabinets.) Last year, it passed a law capping robot numbers to a maximum of three per company and nine in total operating at any given time. Norman Yee, the supervisor behind the legislation, said it was to safeguard people’s ability to walk city streets “without being run over by a robot”.

The fact that San Francisco sidewalks are at risk of being overrun by robots, while in the UK Starship is moving machines from its London fleet to Milton Keynes, is testament to one cause for concern about the robot revolution: that its impacts, good and bad, will not be evenly distributed.

The author of the Centre for Cities report, Paul Swinney, argues that most of the 3.6m jobs at risk in the UK were concentrated in certain cities, including Mansfield, Wakefield and other smaller northern cities with poorly performing economies and a high proportion of low-skilled workers. Meanwhile, the higher-skilled roles to be created are likely to be in south-east England.

The resulting geographic inequality could result in wealthy cities of high-skilled workers served by robots, and the “hollowing out of the middle class”. But Swinney points out that, although most jobs set to be replaced will be lower-skilled, not all will be – and there are elements or tasks within many professions that could be automated without making those professions redundant.

Similarly, Milton Keynes’ accommodation of Starship shows that smaller cities can do more to encourage high-tech investment and make their economies more resilient to change. “Whether it will have a long-term impact in terms of attracting those companies and getting them to stay, only time will tell,” says Swinney. “But for local authorities, it may allow them to capture some of that high-skilled investment.”

As work adapts, workers will, too. Research by the innovation foundation Nesta found that greater importance would be placed on skills such as decision-making and originality in future, across the board by 2030. “In short, the future workforce will in general become more skilled,” says Hasan Bakhshi, executive director of creative economy and data analytics. “But that does not mean the end of jobs that are currently low-skilled.”

The impact of automation on jobs in any given city will depend on its workforce and industry makeup, says Bakhshi. “In today’s globalised world – where increased spending from higher-paid, skilled jobs need not benefit local industry – it’s quite likely that many cities will in net terms suffer while others benefit.”

He points to evidence suggesting that the effect of robots specifically on employment in local labour markets in the US “has so far tended to have been negative” – though technology that enhances productivity could certainly produce a net positive in the long term.

It is striking that, even as companies jostle to automate that last mile and robots make daily deliveries around the world, we don’t know what the impact will be. Going by the reaction to Starship’s machine as it trundles through the streets, delivery droids are still seen as a novelty. For now, the robot is met mostly with curiosity, even excitement. No one expects the harbinger of the robot apocalypse to be carrying a kebab.

Then a bicycle courier spots it at an intersection.

“Oh, fuck OFF,” he shouts.

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