1) Business owners will just take advantage of this (this thread is littered with comments that show exactly this). You will get less pay and make them rich.

I'm really sick of companies that think I will take a 30-50% pay cut for a foosball table and Nerf-gun fights on Fridays.

2) You can gain valuable experience by starting your own company. There are plenty of blogs, articles, and sites like HN that can help you along the way.