I guess that's the definition of 'iconic' - many a time I have approached someone wearing a Ramones or Motörhead T-shirt trying to chat a bit, only to be told 'Sorry, don't know the music at all, but the shirt is cool...'

Gabba gabba hey!

I can wear out a t-shirt much faster than an album, tape or CD, and I am not very caring of the conditions of albums.

I've also never seen anyone slam dance carrying a Ramones album, but I have seen them slam dance wearing a Ramones t-shirt that got tore up.

The last time I went to an Exodus show, there were more people in attendance than sales of their most recent album.

Although the article is unsure whether they sold more t-shirts than tickets, implying that people were interested in the music in a live capacity.

Which is a reasonable implication given that punk grew up around the DIY culture. A commercially produced recording doesn't exactly align with the interests of that type of community, even where that community enjoys the music itself.