I remember when I was a kid (a long time ago now...), Dr. Martens shoes were the fashion, that my school forbade them. We had uniforms, but the rule with shoes was just that they had to be black. I think the ban was on the technicality that the stiching was yellow, so they're not black shoes. And a student tried to loophole the loophole by coloring the yellow stitching black.

I wonder if some brands give out free stuff to "child influencers" so other kids would moan to their parents about buying the items...