Perpetrators: EB Games, Best Buy
Worst Example: Every AAA Release
Pre-orders make no sense for consumers. Sure, it may not seem like a big deal to hand over your money a little early for a game you've already decided you wanted to buy, but the increasing pressure on customers to pre-pay for a product they can't confirm the quality of is ludicrous. The threats of low-stock are the dumbest form of scare tactic to persuade customers because on one hand, it's the store's responsibility to keep a reasonable quantity if they want your money, and on the other, there's no way in hell most of the games they're pimping are going to sell out!
It happens every single year, people get on massive waiting lists to buy collector's editions (or even standard copies) and before the year's through all of the overstock (which there always is) goes on sale for a discounted price. The scarcity of these things is a myth and people need to stop letting retailers scrape a little extra interest cash off of your pre-emptive investments.
The Solution: Stop pre-ordering stuff, wait to find out if it's good!