we live in a capitalist country. Goods & services are sold with the idea that the seller will make a profit. Sure the sales person gets part of the cost. So does everyone else involved in supplying it. Would you work for free?
The problem with ESP's is not that someone gets paid for selling it, the problem is that sometimes they are not legitimate in what they offer. The supplier of the esp will hide things in small print, on the backof sales slips, anywhere where the consumer can miss it. This is what Best Buys just did to me. I wasn't careful enough when I bought it.
Is it a gamble? Sure. so are other types of insurance.
If you buy an ESP be careful! Know what you're buying before you decide to buy it.