He was filled with 'the milk of human kindness'. [=he was filled with kindness; he was very kind]
They 'milked' [='exploited'] their advantage for all it was worth.
greedy landlords 'milking' their tenants of all their money
(..) As for running drugs, what the fuck are you doing? You don't need the money or the pain in the ass. And they will catch you. I haven't needed the money... ...since I took Archie's milk money in the third grade. Tell you the truth, I don't need pussy anymore, either. But I like it. (..)2006 The Departed
(..) You get your period yet, Carmen? You Johnny Sullivan's kid? - You live with your grandmother? - Yeah. Vin, get him a couple loaves of bread, couple half-gallons of milk. Do you like bologna and cheese? Give him some cold cuts. Throw some mayo in. You like comic books? You do good in school? (..)2006 The Departed