No Mustard Only Does It:

There are some hilarious shirts out there that insinuate sexual connotations involved with certain occupational tasks.  For instance, "Bus drivers do it in transit," and "Dentists do it orally" - Check them out here.  Anyhow, here are a few No Mustard Only originals:

Fisherman do it in a boat
Barbers like it hairy
Trapeze people do it in the air
Investors do it "on the floor"

Construction workers do it with a guy jacking his hammer in the corner

Lawyers do it with a cock ring
Engineers do it up the ass
Doctors do it with an octopus present

Tiger Woods does it with 18 holes a day

Butchers do it with their wives, if their wives take a shower first

Gelato store owners do it using tantric methods, like Sting

Teachers do it with a Dr. Seuss book between their but cheeks
Actors do it and never wear condoms! 

Popes do it seldom

Ventriloquists do it with their arm so far up a cartoon's ass that the cartoon can taste fingers!