I do take your point, though I admit I'm inclined to think on paypal as an insurance that I'll get my money back if things go amiss…..and on that note, they have certainly refunded me pdq when goods did not arrive. I can't complain there.
I do think that sellers end up with a lot less than they expect from the price that their goods sell at though.
I like that I can buy from anywhere in the world, easily, simply, and on the whole I have had very little problem with any of it.
It's an enormous on-line marketplace, and well worth a squint through even just for comparison shopping.
M