I think it started as "cool and edgy" thing but showed many benefits to startups. First, if you have many people you can buy alcohol in bulk much cheaper than

I think it started as "cool and edgy" thing but showed many benefits to startups. First, if you have many people you can buy alcohol in bulk much cheaper than usual, if most of your workforce enjoys it then it is cheaper to buy it for everyone than giving increasing salaries a bit for people to drink on the streets which can be expensive. This is especially true for a very young workforce which spends a lot in entertainment. Second, in startups which are pushing people to work for long periods of time, it can be a way to disguise burnout. If you are spending all day in the office you can feel your social life suffering, but they bring your social life to the office, I have my own anecdotal evidence of this. Third, to a smaller degree, people will stick around and while they are not exactly on call it can pop up solutions to problems or new ideas to the office, I've seen many TGIFs crazy ideas get implemented and generate a better work environment, it can feel like a much safer meeting space for people to speak up.