Anheuser-Busch InBev NV prides itself on penny-pinching. There are no private offices for top brass, no lavish parties, and no high-end hotels like the Four Seasons. Guess where SABMiller Plc executives like to stay when they travel?

The proposed takeover of SABMiller by the brewer of Bud Light, Busch and Rolling Rock has set up a dramatic clash of corporate cultures. AB InBev has a long track record of relentless cost-cutting at companies it acquires, and Chief Executive Officer Carlos Brito once boasted that he doesn’t "like people at the company to have fun."

By contrast, working at SABMiller — which makes dozens of brands such as Peroni, Grolsch, Foster’s and Blue Moon — sounds like it can be a blast.

At its headquarters, on a street in London’s tony Mayfair, staffers get an allowance for lunch from local restaurants. The five-star Four Seasons is a hostelry of choice, according to a person with knowledge of the company’s practices. The beer is free.

AB InBev has experience in transforming relatively cushy corporate cultures — Brito ended the free beer benefit at Anheuser Busch — but there’s a deep gulf in attitudes between it and SABMiller. Should its $100 billion offer succeed, that could lead to an exodus of executives fearful of working under Brito’s watchful gaze at the British brewer, complicating integration efforts.

A takeover could mean a "situation similar to what we’ve seen in their past deals, where they cut costs hugely," said Robert Jan Vos, an analyst at ABN AMRO. "It’s a hard culture. It’s tough and very competitive internally."

SABMiller on Wednesday rejected AB InBev’s latest offer, spurning a deal that would create a dominant global brewer. An SAB spokesperson said benefits such as subsidized lunches and free beer support the company’s goal of fostering "refreshment and sociability." An InBev spokesperson said the two brewers share many corporate values and that senior SAB staff would "play a significant role in the combined company."

Brito has frequently extolled the virtue of frugality at the company he built through dozens of acquisitions. "If the guy buying my Stella Artois is paying a premium over my Budweiser, what do they expect me to do with that money?" he said in a 2010 lecture at Stanford University’s business school. "If I have lavish offices and corporate jets and five-course meals when I travel at the Four Seasons, would our consumer be proud if they knew we spent their money like that?"

In the past, Brito has said it’s fine if the rigors of working for him drive some executives away. He’s happy to replace them with hungry recent graduates of MBA programs. In 2010, he deemed departures after the Anheuser-Busch deal "great, because we then promoted people and they said, ’this is my company now.’"