http://www.paulgraham.com/wealth.html
" Instead of working at a low intensity for forty years, you work as hard as you possibly can for four. "
That sounds like 12-14hr/day, including weekends etc.
Now you can see how the rate drops a lot when you divide $2200 by, uhm, what, 70-80hrs a week? It's barely minimum wage.
Of course, you can say 'well, but they're giving you most of the stock if you succeed'. Yeah, but that also means you'll have to pay YC back in hundreds of thousands of dollars if you succeed. (Say YC is getting 5% of your $4 mln startup).
The equity is not guaranteed. YC does not guarantee you'll get huge. They'll just pat on your shoulder and give you some pocket cash in return for a part of your company.
Which is not bad.