Eons ago in its infancy years---(1999 or 2000)---Ebay decided they were getting screwed on people selling an item like, say, an NOS fan belt for $1.50, with a $28 shipping charge. I think their cut was maybe 3.5 or 5%, not sure back then. They were making 50 cents off that deal while the seller shipped the belt for $4 and put $25 in their own pocket. TOTALLY legal at that time. But I saw neon lights go for $5 with $795 shipping charges. THAT's why they changed the business model and started charging their percentage of fees based on "total" sale price which included shipping. I don't know how they were able to pull that off legally, but they did. I guess because it was a fee, not a tax.