CULTURAL OBSERVATION

I went downtown to shopping by bus, then I saw a dog riding on the bus. I was very surprised because animals can not ride in Japanese bus, except Seeing Eye dog, but animals can ride in American bus. I don't like animals, so I hate this. I can't understand why it is OK. If someone has animal allergy, or doesn't like animals. How are these cases? I wonder which vehicle can our pets ride. If it is OK, I don't want to ride the bus in America, so I want to make these place, our pets can ride to place and our pets can't ride and can't go. I think if you want to ride with your pets, you should ride in your car with your pets. So I am thinking it is good to live in Japan. What do you think to ride animals in bus?