That's how the original genies acted though. They weren't happy about their imprisonment so they fucked with the people who made wishes by deliberately misinterpreting them.
It depends on the story. Some genies were evil and imprisoned to stop dicking around, and would screw over anyone who they offered wishes to. Some were nice and imprisoned by nefarious folks to extort wishes from them. These ones would usually monkey paw assholes but not kind folks.