there are ways to make a company look liget on paper so the credit card company will cover there A$$ on that end by showing legal doc's that look liget. Could this type of thing be prevented by the credit card company whit minamal investagation? yes.
Are they going to do that investagating? no not untill some one makes them do it.
for ever person that reports a minor credit theft two others don't even relize it happened.

[edit] It is usualy cheaper for them to give back the money than it would be to prevent the theft in the first place[edit/]