If you're asking me, is it weird, gross, nasty and 100% icky for your man to wear used underwear, the answer is yes. Thrift shop chic stops at T-shirts, pants, sweatshirts and jackets; maybe, and that's a huge maybe, a rare pair of boots. But shoes are the bottom line. As you well know, underwear is home to our private parts. Our private parts, as sophisticated and orderly as they are, still are prone to on going dribble, emissions and all around stank. Even after 100 washes in bleach and high speed rinse cycles who would want to walk around in someone else's former funk hammock? Yes, I get that clinically it's clean, but the human stain remains. It's a knowledge. A feeling. A sense. More specifically though, what is so great about another dudes undies that makes your man dead set on rocking them?
Lastly, if you are very poor or in a desperate situation do not listen to anything I wrote above.