Actually... it does. It's the same reason why Disney goes after Day Care centers for painting Mickey Mouse, yet completely ignores the lead paint covered bootlegged Incredibles toys, Chicken little "Sea Life" stickers, and Pooh plush made from poo fabric. One's just easier to deal with. Pirate Bay, you attack it, it manages to hide itself or attack back. It's much bigger than you'd think. Not to mention Youtube, unlike PB, is a legitimate company. If copyright is broken through them, they stand to lose money if they're sued. I'm sure Pirates bay would throw a couple sacrificial lambs at the lawyers and just move on to something else.