I wear the same thing for work, T, and everything else except for parties: jeans and whatever T-shirt or shirt or sweater is appropriate for the time of year. I pay very little attention to what I wear because it makes no difference.

I would not say that anything anyone else wears to T is inappropriate as long as it works for them. Wear clothes, is my advice. Don't go naked - it is frowned upon in many cultures, and may also cause frostbite.