Hmm... I'm skinny myself and have never considered kilts to look weird on me. I've received plenty of compliments while wearing them (much more than when wearing pants). The only part of my outfit when wearing one that I would think to be odd is the fact that I have a short torso and long legs, so tucking in my shirt in a kilt shows how short my torso is - but in fact, it doesn't look bad at all and even looks better than when I tuck my shirt in when wearing pants, since pants tend to make my legs look that much longer and the kilt somewhat "widens" my appearance.

I do think it's odd that they won't listen to you though. Men's Fashion Rule #1: Listen to the woman, she's right.