Yeah I don't like other people using my clothes or putting their foot in my sneakers or any footwear.
If I lend them something to use it's usually something disposable and I let them keep it... like Bball shorts, a white tee and other miniscule artifacts of clothing that I wouldn't really miss if I were to lose it though.
I don't link other peoples feet in my kicks no matter what, and that's why I never bought used kicks.
I understand those that buy used kicks fix them and clean them up and have them as like trophys just sitting there, but I wouldn't wear them.
My girl's brother be always buying used kicks on craigslist and he gets some really good steals too, but one time he bought the all black Foam One's from someone and there must have been fungus growing inside the shoe due to them not being worn with socks or something of that sort. He cleaned them up and I guess got rid of the fungus and I see he wears them all the time now... they look almost DS now too... to each their own though.