Even some people who don't trust labels trust their vitamin store (GNC...). Many people do not know to question the claims. They think because it's being sold in a store and not on the street, that it is 'safe' for them to take as directed on the bottle.
It's hilarious how people refuse to put any work into their bodies. I went to a company baseball game outing, and this huge woman was asking me how I changed my body so drastically. She seemed engaged and supremely interested in the nutrion and diet discussion, even asked some great questions, only to say "meh, I can't do that, I'm not like you" 45 minutes later! OMFG, i could have slapped her for wasting my f**king time! Besides, what the f**k does "I'm not like you" supposed to mean??