I have no experience shooting bears with bean bags nor do most people, but i have see (on television) in areas like Yellowstone they will shoot bears with bean bag rounds to scare them away and make them afraid of humans. this is after they were caught in a populated area and being set free away from people. it looked very effective.
here is a similar instance where a bear is shot with a bean bag. http://youtu.be/fsfJI-8HFOA
While they may do that, let me tell you as someone who has spent the last four years working 50 miles from Yellowstone, bean bags is not the way? NOT ONE SINGLE park ranger recommends them. In fact, they carry only bear spray. No guns, lethal or otherwise. At the Buffalo Bill Museum in Cody, WY there is a Yellowstone section where there is a video kiosk that tells you just about anything you want to know about what to do in a bear encounter. Guess what, no mention of beanbags.