While the photo makes them look like cards, these are actually issues of "Comic Shop News", a free mini news-paper sort of thing available in comic stores in the USA. They're roughly the same size as a standard US comic book. The issues featured in this image contained a promotional comic by Archie that was later collected in Archie's Sonic Super Special #12.
Naturally, the issues of the paper are a bit rare-er than the actual comics themselves. Info by: