That is true, most people use bitcoin for being involved with crime, or just to steal money. If you join to the deep web, everybody is selling stuff for bitcoins, or just selling credit cards, hacked paypal accounts, and everything. Bitcoin is used for money laundering, that is why nobody can buy bitcoins with credit cards without Identity identification.
I think the bit about not being able to buy with credit cards isn't because of money laundering but because it would make it a lot easier to commit fraud.