I suppose I can understand the conspiracy theory of "they want you to only have work friends", but I really don't understand "they're replacing a good raise with a $100 ping-pong table". It's just not a sane model of what's happening, keeping employees in the building is not inherently profitable.
1) Keeping tech employees in the building is profitable.
2) In tech companies in particular, you don't have to be at work behind a computer to be productive.
Once you both understand that these things are true and correct, you can begin to understand the business of the SV and why these perks come to be.
While people are in the office, they are with co-worker, thinking about work, talking about work, progressing on their work. And the magic thing is you don't have to pay them for it, because they ain't working officially.
A bad thing happen in production late? Fine, they're already there and they won't even think that fixing it is doing actual work because they are already there. That foosball table was way cheaper than paying overtime.
How about serving breakfast at 9 am and dinner at 19? Then people who wants both will stay. Most likely, people who are a bit close to one or the other might extend their schedule slightly just to grab it. But no way they think of it as extra work.
Look around you and count how many people are working overtime on their own, sacrificing their life for free food, a fuzzball table, the expectations of 0.1% equity down the road, the hope of giving a good impression to their manager, the expectations of a raise later for hard work, or the pressure to work night and week-end unpaid on-call.
When not thinking about it, people choose neither money not free time :D