But back to the guys. Of course, when you are alone you can wear whatever you choose, who cares. But if you have company, that's not the case at all. Don't commit a man law violation no matter how long you've known whoever comes over. The least you need to have on is some short or sweats.
Game day!? Man pull out that jersey/ team gear you've been waiting to wear again since last season! That's what it's for! Even if you're a guest, wear your jersey! WE ARE MEN! All about competition, no one is going to be emotional Bc you wore the other team's jersey! If you don't have a jersey, casual clothes are just fine.
Just hanging in the cave, I would say keep it simple, casual and very comfortable! Comfort is key. The Man Cave is like a getaway island so relax. Don't come in the cave stressing, wearing a full suit and stuff. Just relax.
As far as bottoms, wear shorts, jeans, sweats, khakis, etc., essentially, anything that makes you comfortable.