I feel it's a good lesson that people new to the industry often learn. And working for a startup is a lot of fun; you get to wear a lot of hats and a 23 year old software developer gets way more responsibility at a startup than they would working at Microsoft or Google.

If you're fresh out of college, what do you have to lose? You either get underpaid for a few years and learn some valuable lessons (one of which being equity in a startup has a value close to zero) or you get lucky and can retire before you're 30.