How do coupon sites work?

[elcinda]

I have signed up for lots of free coupon sites. One is shopathome. You had to download something and you end up with the shopathome symbol in one of the tool bars. When you click on it and go on the site it says there are thousands of coupons click here. So you do and it takes you to another site that wants your email and name again and offers more coupons. Then the same thing happens over and over as long as you keep signing up. But I never see these thousands of coupons. Its like you are going in a circle because you end up sooner or later back at shopathome.