You work at a startup because you believe in the mission, want to have a bigger impact, your co-workers rock and you want to KNOW how to start one someday. The exit is the gamble for gravy.
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.
Don't take the 30-50% pay cut, use the money to buy your office a foosball table, and go out and play laser tag on Fridays? If you need your officemates to be there, pay their fees, and you'll probably still come out ahead.
i left my electronic trading job, which had great compensation, to move to san francisco and work at a startup. i knew i'd be taking a pay cut, but i did it for the experience, so i could be better prepared to do my own startup.
It depends on what you do at the startup. If you are coding away just like you would at the electronic trading firm, you wouldn't learn much about running your own startup.
Are you involved in customer development, talking to investors, making connections as part of the startup? If not, there's not much upside.
