When dealing with people I know - I ask them to mail me a check .... for strangers at least paypal is a safe middleman. You can also still do the old money order

Don't send chicks - market value fluctuates too much and you may be owed some change.
The person who received your payment doesn't receive all your money via paypal ! Paypal takes their small cut ... if you sent me $50 I would only get $48.75 or something like that .... Then if it was sold on ebay - the seller would also have to have shared a cut of the selling price. Total ROBBERY of the seller.
For buyers - it doesn't matter - except that buying keeps that racket of a business going.