B-sides would have added to the success. Fans would have purchased those singles for those extra tracks that couldn't be found elsewhere.
Artists like The Smiths and Suede didn't just throw their bad cast offs onto their singles as B-Sides, they intended to put album quality material on them.
Re: Ebay sale:35mm Michael Jackson's "THIS IS IT" Rehearsal Film and UNRELEASED Songs (,Bruce Sweide
Yes I was thinking the same. The seller is a big fan. They know their MJ, why all the censorship / withholding info about the content.