Ok, so I don't think this is a crack in my carbon frame, having now scrutinised it a bit closer, but does all carbon mark this easily?

The frame just seems to mark up so easily unlike my painted metal frames that seem infinitely resistant to me sitting on the top tube having a break.

Or is it just a crap finish on behalf of Trek?

Cosmetic marks

If its a mountain bike you will get marks!

Yeah, but this seems like every time I breathe on it it marks. Paint on metal seems much tougher thats all.

Yup – suggest you use copter tape or something similar to protect the lacquer \ finish \ nice shiny bit. The lovely shine on carbon lasts until you actually use the bike. . . . Road bikes wear much better if that's any consolation.

You can bake paint on metal frames, not so much on carbon…