Forgetting things like public relations and marketing strategy, IT IS JUST PLAIN WRONG FOR THE SELLER TO AUTOMATICALLY LEAVE FEEDBACK ONCE PAID, in my humble opinion.

EBay has said, "Leaving honest comments gives members a good idea of what to expect when dealing with other members. Leaving Feedback is also a way to express your appreciation for a job well done." That seems correct to me. Feedback is to give your impression of what type of commercial partner the buyer is. Paying for something is a very small part of the whole eBay experience with someone. The seller should WAIT either (1) till the buyer leaves feedback, or (2) long enough to be sure that the buyer has not unreasonably complained about the item.

Robert
.
.
TONY CURTIS in The Persuaders (1971-72 TV series).
http://www.antiquegamblingchips.com/StillsA_TopMaleStars.htm