Remember when the first Guitar Hero II DLC packs hit Live? The backlash was ridiculous. The calculation of re-buying the entire Guitar Hero track list at the prices being asked for three songs at a time, would have resulted in several times over the cost of the original game. The prices just didn't add up.

Well, with so many protesting the costs, one would think that they'd put a dent in sales by not buying, right? Apparently not.
http://feeds.gawker.com/~r/kotaku/full/~3/155090777/guitar-hero-ii-dlc-goes-multi+platinum-298583.php
So either everyone eventually sucked it up and shelled out the cash, or those unsatisfied with the price were surprisingly in the minority despite being the vocal majority.

Personally, I only bought the pack that had the most songs I liked. I think that's fair enough considering the work that went in to creating packs for Guitar Hero II. If they release more DLC that doesn't suck (like something that isn't for emofag My Chemical Romance fans) I'll probably buy that, too. But only because I'm a slave to the goodness that is Guitar Hero.