in the book Disrupted (about the author's time working at Hubspot), he posits that the free beer offered at startups is to soften the blow of the long working hours and relatively low salaries.
In this case, the free beer might be an intentional way to take "loud room I can't work in", to "laid back atmosphere I feel home in". The latter is false, but it's not as bad as being stuck with "loud room I can't work in".
Different people have different fcactors effecting quality of life. Some people want something more laid back and are willing to give up salary. Others want to optimize salary and work at a big corporation. The market can take a number of strategies—it’s up to the employees to vote with their feet. Given the inherent instability of startups and if they in fact do it less, that vote should be easy to cast if someone is not satisfied.
Drinking or not drinking beer during the times you should be productive is a matter of self-discipline and I doubt it has any direct relation to productivity.
Disclaimer: I work in a private office in a London WeWork and the free beer is a nice to have, even if it wasn't a consideration while picking an office.
