It shouldn't be legal. What else shouldn't be legal is the fact they give you no payment option other than paypal. So you don't have the option of avoiding fees coming and going. It couldn't be any more crooked than it is. When you combine the fees of paypal, ebay, postage fees and fees to withdraw money from paypal so you can actually use it, you stand to lose a lot more from ebay than you will ever make these days.
And if you're a seller they hate you. They are all about the buyer. You can give all the pictures and perfect descriptions you want, and the buyer can receive, open and use the item, and file a dispute if they have buyers remorse and you have to refund their money. You get your ebay fees back in this case, but you never get back your paypal fees or your postage fees. It's a total con job.
Ebay is great for buying, but the sellers that haven't jumped ship yet are either new, selling stolen goods, selling inherited goods, or selling from China. And that's gotten huge. Always check the location of the seller, because these Chinese dealers rip people off all day on there, but people look at the 98% seller rating and assume they are safe. Problem is, they are selling 40,000 items a month, so the hundreds of complaints every month have an almost unnoticeable pull on their rating. But with that many negatives a month, they are shady dealers.
Most sellers and former sellers refer to ebay as feebay for very good reason. It's a criminal enterprise, and they raise the fees every year.
Here is an example of something I sold last January - my final sale on ebay before I left.....
It was a GSA Morgan silver dollar in a case with the original box. The listed value was $475. I got it at a flea market a year earlier for $200, you I was looking to make a decent profit.
I listed it as an auction, and it ended up selling for $340. The insertion fee for me to list it with the pictures and description was $1.20. The final sale fee (which they never actually tell you what the percentage is and that it changes with the sale price) was $48.50. Then the shipping cost for me was $6.52, of which I had to pay ebay an additional $1.32. Then came paypal. Since they deduct their fees from the sale price, instead of waiting for ebay to rape you first, the amount deposited in my account after paypal fees was $298.12. Then to take that money out was another $11.27.
So all total, I bought it for $200, sold it for $340, but after all fees I only received $229.31. A profit of $29.31. Ebay made $104.17 once you deduct postage. Total con job.