Of the horses I used to have, there’s one that I know would have gotten into the feeder (hummer or otherwise) if they could have reached it. :-)
My mom lost a wig (can’t remember why in the heck she was wearing one!) to one of the horses a couple of decades ago - she was weeding/trimming next to the fence & the next thing she knew, her wig was off her head & in the pasture. At least the horse didn’t take off running with it.