We’d occasionally have dogfish brushing up against us snorkeling, the buggers were everywhere. I think they just thought we had a good texture for scratching off parasites.
I don’t think we’re all that interesting to sharks, or that our weird shape and odd electromagnetic properties even cause us to register as ‘food’ properly unless somebody’s particularly desperate. I remember one (way too fast, NO Idea the species) snatched a fish somebody was trying to get a picture of. I felt like I would have been food-sized to him/her, but we were ignored.