Free food has long been a perk of Silicon Valley. On the campuses of Facebook, LinkedIn and Google, employees have access to high-end restaurants with pizza ovens, sushi counters, freshly baked pastries and ice cream.

However, as technology companies come under increasing pressure to deliver more value to the communities they inhabit, cities are clamping down on campus cafeterias in an attempt to support local restaurants.

In a highly unusual mandate, city officials have barred Facebook from serving free food to its employees when the tech company moves into a new office in Mountain View later this year – and the city of San Francisco hopes to follow suit.

Two thousand Facebook employees are due to move into an office in a complex called The Village at San Antonio Center. In a 2014 agreement with the social network, reported by the San Francisco Chronicle this week, the city stipulated that tenants of the development cannot subsidise employee meals by more than 50%. Facebook can, however, cover the cost of employees’ food if they dine in restaurants that are open to the public.

The restriction was enforced after local restaurants complained that free meals at Google, the city’s largest employer, had damaged their business.

“We wanted to make sure businesses that were there were successful,” the councilman John McAlister told the Chronicle.

Neither Facebook nor Google responded to requests for comment.

Tech companies offer staff free food partly because some of their offices were built in suburban wastelands with few local restaurants, partly as a deal sweetener in a highly competitive job market, and partly to squeeze more working hours out of every day.

It’s a popular perk, and one that causes Facebook employees to joke about the “Facebook 15”, the inevitable weight gain in pounds that comes from being surrounded by so many free delicious treats.

In their efforts to satisfy tech workers’ various appetites, tech companies have poached some of the Bay Area’s best chefs, promising better pay and more sociable hours.

The rules for Facebook’s new office are designed to encourage the thousands of tech workers to spend some money in and integrate with the local community, rather than arriving in a bus each day and never leaving the building.

This is what the restaurant industry says has happened in San Francisco, where tech companies like Twitter, Uber, Airbnb, Yelp and Square were offered tax breaks in exchange for locating their offices in the Mid-Market neighbourhood.

“It’s great we’ve had an amazing economic boom where jobs have located into San Francisco over the last several years, but many of these new jobs come with full-scale kitchen operations that make it difficult for restaurants to have a good lunch business and find workers,” said Gwyneth Borden, the executive director of Golden Gate Restaurant Association, a trade group for restaurants in the city.

Borden is one of the supporters of a San Francisco city proposal, announced on Tuesday, that would ban on-site workplace cafeterias.

If approved, the measure would alter city planning laws to ban workplace cafeterias in any new developments, but would not be retroactive.

“This is not a prohibition on catering or providing free food,” said Borden, noting that companies could instead give staff vouchers to buy food from local businesses.

“Yes, we want the jobs but the whole point is you get more foot traffic, restaurant and retail patrons and overall vitality in the streets. But if people are bussed in, go to work and never leave the building, the effect isn’t felt.”

Axing company cafeterias also means axing jobs that, depending on the company, can come with good pay and benefits.

In March, cafeteria workers at Facebook’s Menlo Park headquarters unionised, a move that secured $4.75 an hour in raises, affordable healthcare and a pension plan. The ban on having a free cafeteria in the Mountain View complex could mean losing well-paid jobs to minimum-wage jobs in nearby restaurants.

“We’re not convinced an outright ban makes a lot of sense,” said Ian Lewis, the research director at the labour union Unite Here.

“One of the main problems here is an affordability crisis where working people are getting forced out and we need more good well-paying jobs with good healthcare and pensions,” he said.

“If employee cafeterias provide those jobs that’s fine with us.”

Contact the author: olivia.solon@theguardian.com