When eBay was first created, it was basically sustained by a large group of small sellers. Those were people that were selling items only from time to time, but they were doing this quite regularly. EBay would not have achieved what it did, without this type of users. Unfortunately, it seems that nowadays eBay prefers large sellers that sale at least $1,000 or even $500,000 in merchandise on a monthly basis. Such sellers have discounts that make it quite hard for an average person to compete. After all, the best way to compete is through attractive prices. I know that there are still people who make money on eBay, but it is getting more difficult. Since eBay is the biggest online auction in the world, other auction sites may follow as well.
Some people might not agree that favoring large sellers will have an influence on small sellers, but the truth is that various fees can cut profit by a large amount. Overall, reducing the fees of large sellers will make them reduce the prices making it impossible to compete for regular sellers. Of course, this is not such a bad thing for buyers, because consumers are going to appreciate lower prices.