A bigger problem are the birds that swoop in and flutter over one's food and crap willy nilly. Perhaps restaurants can offer Haz Mat suits to those who dislike our feather friends.
Personally I would rather sit in a restaurant with a dog at the next table than have the couple at the next table coughing, sneezing and talking loudly on their cell phones. Another senario are children acting up and parents shouting at them to behave. I've experienced both and I choose to dine with the dog. When I lived in South Florida dogs were welcomed on terraces and given their own bowl of ice water how outrageous is that.