This is my guess as well. I fully expect the stuff to be harder to get as more people get in. I can already see how it will eventually turns like the steam winter sale. If you link your PSN/XBL/Steam account on the site you can get XP for doing specific achievements. It's basically a not so subtle way to make you buy games to get rewards. So far the stuff require very low level like 10-15 but once more people get in and the site gets older, it will probably be difficult to only level up with Trivia.
It's obviously some kind of market research experiment too. They won't let you redeem prize if you don't specify your favorite gaming platform. They also have a showcase section where you can watch trailers for ME3 and FFXIII-2 (obviously advertisers money) and are trying to push some Click magazine you can get for free. Some threads on the forum are also suspicious. Would you make a thread saying you are excited to preorder FFXIII-2
?
The upcoming 3DS deal is good though. 99$ for a 3DS is nice.
Also if you are in QC and try to register for the cinemanow perk (you can't as it's not available) you get a funny email saying the AI is not satisfied with you not getting the prize and will try to work something out.
The nice thing is that you cannot hoard the stuff. RFD is thus out of the loop. It takes a while to get the required XP and you must be a gamer to know the answers as the questions are timed and you don't have time to use google.