In 35 years of multiple annual backcountry trips in Maine, I can only recall a single bad bear encounter, and that was one that was hanging around a garbage can in Baxter State Park. Baxter has since converted to a carry in/carry out policy, which seems to have eliminated what used to be a common problem.
I have never hung food or taken any other particular precautions with food on my Maine trips. Most of my friends don't either, and I can't recall anyone with stories about food-habituated bears here.
But when I moved out of state and tripped other places, I recall bears after food in camp on a regular basis. By far the worst were bears in Porcupine Mountain State Park in Michigan's UP. (I believe the problem there is the high incidence of brats in camper's food packs at campsites. Those bears get a taste for good sausage fast!
) But I also had bear problems in the Adirondacks, in Great Smoky Mountain National Park, in Yosemite. I never lost food to a bear, but had them prowling around the campsite and poking around my hung food a lot.
I'm not sure why we don't see lots of bears at campsites here. It may be simply that use is more spread out over a big landscape so bears get less habituated to people. It's certainly no lack of bears in the woods.