It's always nicer to sit outside. The sun and the bright light can change the feelings so much. Men are allowed to sit with their breasts bare,I think it's good. It's not like that with women, maybe that'll change if it's not sexist. I think everyone should feel good :).
I guess that is why most people prefer to sit outside - except when it is Winter and it is too cold to sit inside.
If I were the owner of the establishment, I would prefer that all my guests be appropriately dressed. I think it is common courtesy. Also, to be fair to both sexes. 😊