They did not "give up" on Majora's Mask. They just put it aside 'till the end, because it froze on them four times!
@Atomheart: It was never originally a charity, it was there pizza fund. And they decided to give the rest to charity. Also, they are playing each zelda on one console, in order.
@Everyone who says it's lame if they don't finish: You go attempt it. You probably couldn't even beat the first game without falling asleep!