I think the chargeback scenario here isn't cards which are actually stolen. It's that someone makes a purchase, their spouse notices it on the credit card statement, and they deny it.

Then in order to sell the lie to their spouse, they call the credit card company and say, "Of course I didn't make those purchases! I would never do such a thing! I'm not some kind of pervert! Remove these charges immediately or I'll close my account!"

And then the credit card company's thought process is like, "Well, you probably did! But we can pretend you didn't, if that's what it takes to keep you as a customer so we can keep making money off you."