Band T-shirt thing only happened once in a band I was in:
One of the guitar / singists had written a song called 'Cartoon Victim', and decided to have their own T-shirt made for a gig with the title emblazoned across the front.
We ripped the pee out of him before the gig, and even more afterwards when someone from the audience asked who 'Car Tim' was - his guitar strap covered the rest!
Never again!