Could it be that people who've done the shop hop in the past have complained? I would think that would be the only reason a shop would be dropped. I could be wrong though, it's happened before.
It may not matter in the future. In our area fabric companies used to donate the fabric for the shop hops. This year they only donated 50% of it AND limited the choice of fabrics. They picked the fabric and said, "This is what we'll donate at 50% off but you must use these three fabrics and our blenders." Since the fabrics and colors they chose weren't very pretty it was a challenge for the shops to come up with a pattern that looked halfway decent. I didn't do the hops. (there's two here)