Well it's just a bug that happened to slip through PBE because it's an inconsistent one, and generally only happens on (or against, depending on your perspective) lower-end computers. Even with low-end computers, it doesn't always happen, and it's difficult to consistently replicate, which I'm assuming is part of the reason it's taking a long time.
No one said you had to immediately buy the skin upon release though, and with just about every other thing Riot had to take down for bugfixing or just in general the concept that brand new releases for anything (not just League) online might be bugged is something people should keep in mind. Sure, you can ask for compensation, but I don't really see why Riot needs to give that. Yes, they should have done more bugtesting which is their fault, but the rest isn't.
I'm one of the people that also bought the skin immediately upon release, but I'm just sitting patiently and playing with other champions or the Blood Moon skin I have for Thresh while I'm just waiting for it to be fixed. But again, there is no need for compensation, because there is no burning need to play that particular skin. The last time I remember they gave compensation was with Gangplank because he was going to be used in a tournament but then was disabled for bugs. Skins don't have any impact on the game itself, so it's irrelevant.
