Soliciting opinions on the necessity of credit card info when only selling

Thats I think where I was confused about my fees selling on Audiogon.

Audiogon charges fees either upfront or post sale yet you have to pay a fee upfront for the listing.  
I guess your real choice is pay up front then pay up front again or pay up front and then pay again post sale.

Surprised there isn’t a charge somewhere in the middle