The other thing unique to the priceline/La Quinta deal was that your reservation was (supposed to be) non-refundable, non-changable. And it was expensive enough that you would have been foolish to book more than what you actually expected to use.
Much different from, say, the Marriott/New York deal earlier this summer, where you could reserve large blocks of rooms with no obligation.
This was partially why I would have guessed that priceline would honor their deal while others have not. Alas, they did not.
Regardless, human nature is human nature, and asking a large and anonymous group to not be greedy is a waste of time. Most people who learn of a deal like this will "profit maximize" for themselves and not worry about the herd. That sounds bad, but I don't really blame them.