We recently had to recover several hacked accounts for an elderly relative (let's call him Bert) after he reused the same password in dozens of places.
One was interesting. We found that someone had taken over his Paypal account years ago and was using it for occasional small purchases amounting to about £100 a year. The means of payment attached to the account was owned by a third party, Connie, so it wasn't costing Bert anything.
I wondered why someone would do this. I speculate that someone (Alice) is running lots of stolen PayPal accounts attached to lots of stolen credit card details. Alice makes few enough purchases through each one to make it unlikely that anyone notices the theft. If Connie does notice it, she blames Bert, whose full name is on the PayPal account; she doesn't blame Alice, whose name doesn't appear anywhere. If Alice loses access to one PayPal account, she doesn't really mind, because she has 99 others she can keep using. I'm guessing Alice does very nicely out of this scam.