Well, I work as a picture framer, I guess it's blue collar work, (at least it's Blue collar pay!) but not really heavy physical labor. I would wear a kilt there if I could, But my company has a strict dress code, and in the frame shop there are safety issues as well, as glass is being handled etc.. So long trousers are required. We do get a little messy, but we use knee length aprons. If I were allowed to kilt up, since I don't like Utillykilt type styles that much, I think personally I'd go for something that was easy-care, and since a sporran might get in the way, had some pockets, but still had pretty 'traditional' styling like offerings from Neokilt or Freedom Kilts