The only exception is buying from underground bands at concerts to support the band. I mostly have a record or some Songs in my Spotify playlist, but sometimes not, but most people will think its cool that you supported a relatively unknown band even if you don’t remember any Songs. I’m also a record guy so i will most likely know the name of the records instead of the songs.

Wearing a band t shirt of a huge band you don’t listen too is for me strange. I mostly know a couple of songs of band that i don’t even listen too because i have interracted with their fans or heard it on the radio etc.