Most people would probably say the dog and pony are not quite interested in entertaining you and if enough of those people decide forcing them to do it anyway is immoral, then eventually by way of law you won't get to put on your show. So the underlying feelings of the animals are in fact, pretty meaningful.
If your only criteria for the ethical treatment of others is their ability to convey their thoughts, then I'm scared for what you think of how we should treat the mentally incapacitated.