I never go to someone and say, “I think you’re better looking than so-and-so.” I’m about 200% sure you can compliment someone without putting someone else down; unless you’re just doing it out of spite for the other person—in which case, sort your issues out in a different manner.
But while I have no problems with anons thinking my friends look better than I do—because my friends are qt pies—I just don’t understand the need to randomly say, “you’re cuter than soratane.” Have I offended you in such a way, anon, that you really felt the need to try and knock me down a peg? Honestly. I doubt I have.
I think somewhere along the line you’ve just forgotten that I’m a human being. Specifically comparing others to me (especially my own friends) is just as rude as if I were to announce that your buddy’s face is specifically better than yours.