Many missed the point of this. Don't know if it is legal but it isn't ethical. their fees should be based on sales price (and they used to be). Then the figured out that most won't notice if they charge the fees on the shipping too. So if your shipping is $10, you'll have to charge $12 or pay $2 yourself. I guess they argued that they do this so you won't sell a $10 itm with $2 shipping for $2 with $10 shipping. So 1% of ebay sellers tried to work the system and the other 99% get to pay and ebay reports an earnings gain.
As for sales tax, ebay keeps all of that and sends it to the state etc. so I don't think they are charging fees on it. But if they caluculate your fee based on it, then they are really just adding a defacto fee increase.
Jerry