In my youth I fed and cleaned the cages of the bears in a local zoo. They had all been hand raised and were used to people, so I was really only in danger from the Kodiak Bear. The black bears and the grizzly would roll over on their backs and insist that I scratch their bellies with the rake. Sometimes we played, but bears are like big, powerful, dogs who don't always know their own strength. I was never seriously hurt, but watching the grizzly cower away when I told her "Bad girl!" was a definite sight to behold.
I don't expect wild bears to respond like that, but I always remember the tame bears when I encounter their untamed relatives.
And note: I'm still alive.