Shill bidding is bidding on the auction by using other people or accounts to drive the price up. Shill bidding is not the same as auctioneer bidding on the item. Ebay only talks about shill bidding, not self-bidding as self-bidding is not possible on their platform. Shill bidding is a crime, yes, but self-bidding is not. Otherwise many auction houses in Europe would operate illegally.

Hope the difference between auctioneer bid and shill bid is now clarified. They're totally different things. First one is a type of concealed reserve price while the latter is dishonest activity to fake price up.