Jonah Hill is not required to provide autographs to his fans. Doing so might be too time consuming and too much trouble. Instead, handing out wise-cracking business cards is a good alternative to autographs. The fans get something from Jonah Hill and Hill gets to easily pass out the business cards.
Jonas Hill is a comedian. What don't people get about this? I think it is hilarious that he keeps them on him at all times. In 20 years, it will be a collector's item. If it turns out he really is a snobby "star" then I think we will figure that out too.
No, Jonah Hill can hand out cards instead of autographs if that is his preference. Autographs require either always having a pen handy or to use someone else's pen. It takes time to write an autograph, because they are inevitably personalized to the one who wants it, and it doesn't take very many to burn up a lot of time. Cards are an efficient way to thank a fan and move on quickly.
There is no rule saying that a celebrity must provide autographs to their fans. If Jonah Hill would rather hand out cards than sign autographs, that's his business. Maybe he has more fun with the cards. Maybe it's something personal to him, and gives him an unique touch. Let the man do his thing, his way.