Ok I'll have a quick stab at this one.
I prefer to just consume books, movies etc. and not analyse too much because... well I don't know why... no need for me to think that hard if I don't want to and perhaps most offerings are not worth the analysis.
I like reading books but I dislike doing book reviews. Same for TV and movies most of which just aren't up to the standard that I like and that's not my fault or necessarily a bad reflection on the movie or whatever... it's just true. There are exceptions.
Anyway True Blood is something I enjoy consuming and I make allowances for some of the rather large holes in that universe. They seem to quickly come up with fast explanations to explain away stuff which can seem a bit contrived but I'm happy to let it go. Over analysing would kill it and I'm going off to watch the opening ep for season 2 right now.
Unless vampire hairs and bodies are utterly immutable and resistant to harsh wear and tear then they must regenerate in some way - no doubt by drinking blood. Getting punished by being locked in a coffin or some-such without access to blood causes them to degrade rather much.In this show previously I seem to remember Bill nearly melting due to excess sunlight but he made a fast comeback to English good looks (yeah right

) after lying in the earth for a night (I think... can't remember exactly). Therefore it appears that as a vampire you can do foils in your hair or alter your cosmetic regime but by rights after you jump under the dirt for a nap you should go back to how you were when you were turned. Bad luck if your roots are showing and you don't like that.