I have not seen one of these fakes with a Holsum back til now, but they are seen with Henry Johnson, Kendig Chocolates, and *Oodles Chocolates ads on back (all stamped, not printed).
I first saw them about 2001 or so and got burnt on a Kendig, I believe Leon had an *Oodles Chocolates too and learned the same way. (*edited to correct name)
In person they are obviously fake, the stock is not right, the picture is low quality and the cards often have a slight gloss like shellac and sometimes yellowish tone.
Here is one of a few posts on them
http://www.net54baseball.com/showthr...dig#post475942