He's turned into Jake LaMotta
Is he purposely screwing up his legacy? It's like he's trying as hard as he can to end up like the famous last scene in Raging Bull. A washed up human being still trying to be relevant. I used to admire him so much, now I see a movie and he's in it I instantly assume it's crap. Man, if you told me twenty years ago he'd be considered a "joke" I wouldn't have believed you. And people thought he was slumming when he did the "Focker" movies! Those are friggin gems compared to Bad Grandpa. Bobby, you've hit rock bottom. You need help. His career ended in the late 90's. Since then it must be a doppelgänger and the real Bobby D is tied up in a Brooklyn basement.
Some people say he needs money, others tax problems, but as one poster suggested : Drugs. Because at this point it's as good an explanation as any. What a shame...