Hi Chris and welcome to the forum,
That could well be the most obscure, yet interesting question I've seen here in a very long time lol. The short answer is, I have absolutely no idea.
I doubt that sort of coverage exists, at least something specific to drop-shopping itself, however, there may well be some liability coverage available if that is something you are concerned about. I would suggest speaking with an insurer about your options on that one, they will be best positioned to advise you on what sort of liability coverage would be best, if any at all.
Cheers