Money is money, they're getting the same amount no matter who it comes from. All they have to do is say "sorry, we oversold" and give you your money back. /snip
Your looking at it the wrong way. You are a potentially a big source of income. Every customer is averaged at around $1000 income for the business. So losing 1 customer means losing a potential $1000. Then comes the devastating word of mouth, which could also make the company lose more customers which means more money.