milk (someone or something) for (something)
To try to get as much of something from a person, thing, or situation as possible. The company used to make all sorts of innovative games, but in the last few years they've just been milking the same franchise for as much money as its fans will give them. The candidate has been milking his opponent's scandal for press coverage.
milk someone for something
Fig. to pressure someone into giving information or money. The reporter milked the mayor's aide for information. The thief milked me for $20.