Colloqialism from the American South, literally means don't bit the hand that feeds you.
BILLY: God damn, woman! Old man Winter's makin' me work on the weekend ho'ing his damn soil!
SUSIE: Well is he payin' you that there overtime?
BILLY: Yeah. So?
SUSIE: So shut yer trap and put on yer work boots for an extra day's pay! We need to get little Billy new shoes and our roof busted a hole again!
BILLY: Aw, Susie-
SUSIE: I said shut it! Don't kick yer coon dog!
Someone who is addicted to obtaining money and building wealth. A money addict and fanatic. Breadheads often work more than one full-time job, and some even participate in illicit activities to "obtain the bread".