Probably because if PP finds out a seller is abusing personal in this way, they will get shut down.
Exactly, if someone is abusing it, they will get a warning and may be told that they cannot use personal pp. I know at least 2 dealers who were told they could no longer use it for "excessive use". However, whenever I called about the charity threads and said we were selling books, I got the same response, that it was not a problem and we never had a problem except for the first time, when we hadn't called and someone's account was temporarily locked, until we explained. That's the reason I or someone else calls each time, to prevent that.
If I'm ever involved in another charity thread, I plan to do the same thing, call them and ask.
So although I'm not looking for arguments, I think the word "thief" is a bit strong.
I hope you will atone for your sins at some point. May god have mercy on you.