"Cabbage" & this other basic salad ingredient are both slang for paper money
In diner slang, apple pie is "eve with a lid" & to "put a hat on" her ... "Cabbage" & 
this other basic salad ingredient are both slang for paper... [DOC] [TLE] Cabbage | Define Cabbage at Dictionary.com [PAR] 2. the head or leaves of this plant, eaten cooked or raw.