Dumbo t-shirts

I'm sure you've seen them. I have: T-shirts that announce "Mary and the Sheep Road Crew" or "Dive Crew" or some other 'I'm in a crew' slogan.

Why do people advertise that they are part of a bunch of menials? Road Crew? Dive Crew? people who don't, as a rule, think of anything, they just push and carry.

The best slogan I've seen is:

"No I will not fix your computer."

Presumably worn by a computer scientist.

Here's another:

"No, I will not join your boring conversation."

or

"Go away, unless you are interesting."

or

"Don't be ordinary, have an idea."

Such are endless, and they get away from the 'I really want to be a hod-carrier' type of slogan.