I read an article somewhere talking about the proliferation of bootlegging and how it's cheapened the owning of even the real thing. There was also a side bar telling how to tell the real deal from the fakes. I personally would feel really tacky carrying a bag/wearing an item that was a knock-off. Louis Vuitton bags aren't really cute, but it's the name that makes them sellable. If you buy a fake you're copping out.
Then again, I'm not much of a label shopper. I don't care if it's a $3000 Versace dress; if it doesn't look good on me, I wouldn't buy it. Not to mention I don't have three grand to be throwing aroudn these days.