There are certainly a bunch of counterfeits being listed as reprint for this card, and they look good too. This is surely a shame, and is destroying the vintage market. In baseball, I don't worry too much about counterfeits until I get into '60s cards. This is a late '70s card that is seriously being counterfeited. I tend to report as many counterfeiters as I can find, but if they are at least saying "reprint" on their listings, then there's not much that can be done.
The cheapest "Buy it Now" payton I see that claims to be original is going for $100. The corner wear looks real, but the glossy crease is a little suspect. There's no dirt on this card, but looking at higher-priced graded cards in low grade, this card seem to be dirt-proof. For cards in this price range, I think the seller should be showing the front and back, which the seller of the $100 card is not doing. This is a shame for collectors of Walter Payton RC's. I'm having a similar difficulty with the Nolan Ryan RC of 1968.
This all feeds into why I'd prefer lower-grade cards when it comes to high-value stars. Although people can try to falsely age a card, it is generally easier to tell the difference between real and fake for lower-grade cards.