People are able to buy on the cheap b/c of DVD's own doing. They stripped the (perceived) perks from the resales. They stopped with ROFR. If they really cared, they'd have kept them all the same and ROFR'd contracts across the board to make the price difference nominal, and the benefits of buying direct sellable. If they kept SSR at $100 direct but maintained an $85 floor resale via ROFR, but waived closing costs for direct purchases, threw in a $500 Visa giftcard and allowed for a 20 minute close instead of 2 months, they'd have most people buying direct.
They did all they could to make resales cheap, it's not like the could possibly be surprised that this is the end result.
Also, the 7 month booking window is the only reason to buy at BLT, or anywhere for that matter. You want to stay at BLT? Guarantee it by buying there; otherwise you might miss out at 7 months. They want people switching over. They want to tell the new buyer that BLT is filling up at 7 months. This helps them sell.