The original question was...will the seller lose money if he limits sales to Paypal? That's the issue.
It does not matter how you sell on eBay as that is your option.
If you limit your buyer options then you will lose overall!!! Simple!
If a seller stated that he would ONLY ACCEPT CASH...then he would lose sales.If he stated that he would only accept cheques...then he would lose sales. If the seller stated that he only accepted colored beads...he would lose sales.
My complaint is simply:WHY LIMIT THE POTENTIAL INPUT OF MONEY that you could get by isolating other forms of payment? Allow your customers options and you will make more money.
And as for this nonsense about having to go to the post office to mail things out of country or whatever....boo hoo! If you are in a business,then you should bend over backwards to maximize your sales.This is what separates successful sellers from....well....people who sell.
You do not have to go to the post office every day.You can tell your buyers that you mail every Friday or Tuesday or whatever.
This excuse that sellers use about having to go to the post office just gets tired after awhile AND.... this is not an attack on you personally....it is a criticism and attack on the idea.