you should search for how many people are getting scammed because of charge-back. just google it and see some forum posts on social places like blackhatworld or reddit. there are a lot of people who have been scammed because of charge-back, the scammer buys the goods and then easily charges back and there is no way of proving by the seller in most of the times.
Correct. And it's worse than you can possibly imagine. I have a hundred examples. I won't go into details here because I don't want to give any scammers ideas. But I could easily chargeback any online purchase I've made. I can keep the merchandise and I get all my money back, at the merchant's expense. The credit card companies don't care because they've shifted the responsibility for fraud to the merchants, yet they refuse to give merchants the tools needed to fight fraud. Scammers love credit cards.