from my perspective, if the tourist chooses to wear a kilt when on holiday in Scotland, he should wear an 8 yard wool kilt with knife pleats, coloured hose worn with flashes, a day sporran, shirt, and fleece or other comfy jacket, not a pc, tweed jacket would be best, leave the ghillie brofgues at home, he should relax and enjoy himself, he should wear the kilt as if he has worn nothing but the kilt, and he will fit in just fine.
No animosity will be shown, he will be made to feel very welcome.