Babysitters charge by the hour. Bach did it with the organ. Bailiffs always come to order. Bakers do it for the dough. Bakers knead it daily.
Ballet dancers do it on tip-toe.
Banana pickers do it in bunches. Band members play all night. Bankers do it for money, but there is a penalty for early withdrawal. Barbers do it with Bryll Cream. Barbers do it with shear pleasure.