There are two sides to every transaction 1) Buy, and 2) Sell A shorter is simply selling first then buying. The shorter is providing a service. When there aren't enough shares to go around it's like having bonus shares. Indeed it's like betting. Everything you do in the stock market is like betting. If you’re long you’re betting it will go up If you’re short you’re betting it goes down. I find it ironic that you're condemning such an action while investing in a casino stock.