From my understanding in the very beginning of eBay they didn't take a fee off the shipping cost but then people grossly abused that and would charge really high shipping and a low item cost to avoid fees.
Now every single reseller platform out there will charge you a fee on the shipping cost to avoid a similar scenario.
Also eBay really wants to encourage people to use "free shipping" And they say they will even promote your listings higher in search if you do so. It wouldn't make any sense to punish those that use free shipping by charging them a percentage of the shipping fee that's built into their price but not charge other people a fee on their shipping fee that is seperated out.
What people are really mad about these days is the fact that Ebay is charging fees on the sales tax that are collected (and the seller never sees). But I guess it's pretty standard in retail for payment processors to charge a fee on the total amount the buyer pays including the sales tax.
Like many have said it's eBay's playground and they make the rules and there's no fighting it ....you either agree to it or you can try to sell somewhere else. But like I said before, you're not going find reseller platforms anywhere that don't charge you fees on shipping.
