Didn't look, but I assume the buyer premium is +/- 20%.
Auction houses are in this to make money:
Sell a questionable 52T Jackie raw for $1,500 and make a $300 fee.
Sell a NM graded 52T Jackie for $7,000 and make a $1,400 fee.
Why grade them???..maybe they are in it for the love of the hobby only?