Because they knead the dough.
I always loved this one: (works better said out loud of course) What do you call a fish with no eyes ... A FSHHH
Plantaintions.
Loafers.
To win dough.
Because he really kneaded the dough. (please forgive me for that awful pun)
You, knead me.
Oh baby ewe...you got what I knead!"
I don't knead you anymore.