hiderm

I want to understand how these sites or companies ...

I want to understand how these sites or companies make money from the users and how they can pay out $25.00 per month? I would like a site like theses but have no idea how - can you help?

http://gasandgroceryheadquarters.com/

http://gotgascert.com/

http://www.freegasolineamerica.com/

http://www.monthlyfreegas.com/

http://www.claimyourmerchandisenow.com/

for example a car repair shop or tire dealer places an advertisement that states " buy 3 tires get the 4th tire free and $300.00 of free gas" just as the web sites i have used as examples in the request for you to quote.

lets say 200 tire customers buy 3 tires get 4th free and get into the free gas program. 200 customers times $25.00 per month = $5,000.oo. How do they do this? I want a site to do this also.