Corey is just looking to rip off everyone he sees and he doesn't ever know shit about the items.
The guy from Hardcore Pawn makes Corey look like a saint.
There is more than one show about pawn shops? 
Pawn Star is hugely popular, one History Channel's top shows. Of course there's going to be imitators.
truTV's Hardcore Pawn is absolutely dreadful, however. Les, the owner, is oily and loathsome, always giving people far less for their garbage [generally old TVs, VCRs, jewelery, and other cheap junk] than it's actually worth, [which usually isn't much] and his clientelle are almost exclusively poor inner-city folk and crackheads. It's set in Detroit, by the way.