Disney kind of creates this by setting high limits on stuff like this. I think with the ears you could buy a max of 10 at a time and there was a video of a person at one of the shops cleaning out the displays. They did the same with the limit edition popcorn bucket cauldrons last year. You could buy 2 at a time but they didn’t stop people from going from one cart to another. I saw some guy walking out of the park with at least 10+ lol.