anyone can post anything on stubhub, ebay, CL, etc. and they do.
essentially, the scalper is promising that if you're stupid enough to pay his ridiculous inflated prices, he'll find the tickets for you. chances are, he'll just buy them from another scalper after tickets have gone on sale, and pass them on to the paranoid sap who paid his pre-onsale inflated price. they're praying on people's fear that they won't get tickets at all, so they post those "tickets" for sale before anyone has tickets in hand - including the scalper himself.
there is no grand conspiracy. it's simple greed. but i'm told that if you make yourself a hat out of aluminium foil, it'll protect you from the scalpers' mind-control rays.