Usually on high end cards, there will be profits to be made given the growth of the hobby in the last 20 years. In a perfect world, you are suppose to be taxed on the profit and give that to the government on an individual card basis. That 1st edition base set PSA 10 gem mint charizard you got for $1,000 back in 1999 and sold it for $350k today, well Uncle Sam wants a piece of the $349k of profit that you just made.
That’s one of the reasons why people prefer to do private sales. Same reason why people prefer paypal FnF instead of GnS as no sale information is remitted to the government.
Gary King Pokemon even mentioned it in one of his posts a while back (link below).