I'd say it's almost something of a rite of passage to get taken advantage of if you're young and working in tech startups. Usually this is in the form of abysmally low pay, along with "Sweat Equity":

https://en.wikipedia.org/wiki/Sweat_equity

Of course, the startup doesn't go anywhere, and your sweat equity never materializes, so you're left with just the pitiful pay.

I went through this in my late teens/early 20's, along with many friends.