I am not sure where the largest concentration of Trophy bears lie. I know that the north east receives a lot of hunting pressure because there are affordable outfitters within driving distance of the states, so many hunters from the tristate area visit.
I believe the potential for a 400lb bear always exists, but a 150-200lb would be the norm. It's tough also as many people such as myself only hunt infrequently so judging size is very difficult, especially in the spring when the hair is so long, its like a skinny person wearing a fur coat.
As far as baiting in general, I think it gets a bad rap. I have a friend who live in TX who works on and near many of the more famous ranches in the areas where the famous Muy Grande grow. We both grew up in the north east so we were biased against these canned hunts.
After a few years there and geting permission to shoot some management does and bucks for the ranchers, his opinions have changed. Many of these ranches span 10,000 acres or more, and the goal is to raise trophy animals. Trophy animals take a lot of nutrition and cover to grow, and supplemental feeding between annual crops insures this. Smaller young deer run to the feeders, bu the big boys definately do not. Some only feed at night.
I'm kind of against fencing as a wildlife management program, but If I spend 50k a year to feed and raise a herd of trophy animals for 10 years, I guess I would not want them walking off either. Off the topic, sorry.