I didn't register for the website, but I can explain how they make money, and how they (should) be paying you:
Its called Affiliate Marketing. There are many ways that net-based businesses try to acquire users through standard means, such as putting banner ads on websites, video ads, and Cost-Per-Click ads which pay only when a user clicks the ad.
Then there are affiliate offers - they pay out only when a user signs up to a service. These kinds of offers are worth far more than standard offers, usually in the area of $1-$300 depending on what the user is getting.
Websites like Lockerz, I assume, generate these offers among other things, and promise to give the user a cut of the revenue they earn. On some sites, its very legitimate, but on others it seems to be really questionable like Lockerz.
If you want actual money, then there are other sites that pay better:

This one should be very similar to Lockerz, but they actually pay out.

Kind of difficult to get money, as you have to read ads. If you get a few people to sign up under you, it can be a decent money generator.
If anyone is interested: I am building my own system like these two. The difference is that all the money earned can go towards charities - so you could sign up for a survey website, and donate the $1-2 to a charity.