Should parents be allowed to make their kids work at their business for no Pay?

I say yes, depending how intense the work is.
I currently work for my parents business with no pay, but why?
My parents have given me a home, food and clothing - so it seems reasonable to pay back the favour, to me anyway.

They created you, you're their responsibility until you're old enough to go out on your own. Then you can return the favor. Just my opinion anyway.