This is outrageous alright! I'm one of the few people around who doesn't buy/sell on e-bay, so this may be a stupid question. Are they the only site of this type on the internet? Aren't there other alternatives for these people to use?
The past seven years I've used ebay only once for purchasing curriculum/teachers texts. I sell/buy on vegsource.com/homeschool and theswap.com. There are others but I've had the most success on the two listed.