There is nothing worse than a drunk, and there is nothing that a drunk hates worse than a machine that is sober. We had several bad experiences with drunks who did everything from pouring a drink on a robot to pushing a robot down a flight of stairs. On one occasion, a drunk became belligerent and followed a robot, trying to start a fight. Desperate to avoid trouble, the robot turned away without saying anything whenever the drunk approached. Whereupon the man tripped over his own feet and passed out on the floor.
Some forms of life are harder to fool than others.
Animals are not as easily fooled as people. They know immediately that a robot is not alive, but on the other hand, they have never seen a walking chair. In general, while they don't particularly like the robot, they aren't afraid of it. They just want to be left alone. A film crew came to us one day and, among other things, wanted to film some shots of a robot walking a dog.