I think you said it when you said familiarity. They are afraid of us because it's been ingrained into them for centuries.My wife walks the trails regularly and has a couple of bobcats that are quite happy to meow/grumble with her and just sit on the trail grooming while she walks by. I wouldn't recommend it to others, but they have it worked out. One of the local red tail hawks will also chatter with her when she comes into view. "Animal magnetism