I agree with Harry. eBay is not perfect, but it the closest thing we have. They are, by the fact they are a publicly traded company, required to maximize profits. If something in their fee schedule hurts that profit margin, it will be changed. As long as they are making money and increasing the value of the stock, they are doing EXACTLY what any business is trying to do. Try to sell your models on emodelcars or another site and see if the difference in fees offsets the difference in final selling price.
Emodelcars is a good idea - unfortunately, not good enough to sustain itself. Would I buy and sell there? I would, if there was anything to buy or anybody to sell to.