I can't see the prices because I am not a member. However, I suspect it is a gimmick. The fact is, the cost difference between a 3 day pass and a 10 day pass is about $26. WDW hits you hard the first three days of your pass and then they charge you just a couple of bucks each extra day you stay and play. I could start an ad that says "Pay for three days and get an extra seven days for just $26!"
I should add that this pass may very well save folks a couple of dollars but not any huge savings. I would bet that some of the reputable sellers may have a similar price folks could get without joining a new group.
Still, it didn't hurt for the OP to put the information out there.