Next, these things are to try to encourage the retaining of the college mindset. Aside form the "play hard" there's the "work hard" - the all night cramming that you had with college gets translated to working all night to meet some project target date.

Additionally, by establishing these pseudo-third places, it encourages the people who use them to be part of the work "community" rather than the civic community (where the hacker space or coffee shop is). This in turn makes the people who work there more isolated from the people in the community and has an impact on the third places there as there are fewer people in the civic community who use them (when they are provided free at work). Yes, you would rather use the local hacker space than the one that FB has for a woodshop - but that isn't true of a fair number of people.

Lastly, these perks aren't things that the company values too highly and thus is apt to remove them when times get tighter. Establishing those perks as the norm (see Basecamp with its combination of company forum pseudo-third places and perks) and then changing how they're done or making them location specific (FB employee in SV gets a woodshop, while the remote worker doesn't) will create discontent later down the road.

---

I believe that companies that are offering these perks and pseudo-third places (as perks) are finding that the trouble that they cause is more than the value they provide to their employees from the employer perspective but are having trouble withdrawing.

The SV style perk - I believe - is a liability to a company. While it may improve employe retention a bit while it is active (and I really question that in as junior dev tenure has been dropping combined with an increase in remote work), removing it can result in singicant discontent and hosting it increases the issues that HR has with maintaining it.