Well, I wish everyone the best but I see all sorts of problems, including people with allergies, people with phobias etc. I would expect..not really..I would hope.. they should be informed of the presence of an animal on board..this is not a situation where they can leave if they find something is going to be harmful to them..they are stuck. I would hope that every animal that is a dog would be muzzled or caged, and other animals as well..my brother had monkey bites that caused him all sorts of problems. People are going to claim that they need their boa constrictor (and they do) as a service animal. Various exotic animals are being defined as companion animals, for good reasons..and undoubtedly help the people they assist..some people with service animals by definition have some sort of problem..can they all control their animals under each and every circumstance? Does the airplane carry tranquilizers to be used if necessary..on other passengers I would think if they started to have a panic attack or something from seeing a poodle....

What does an animal use for a bathroom on a long flight, or just if it gets airsick or whatever? What about odors? What about barking or crowing or whatever?

I know official service animals are of the right breed for the task, carefully trained etc...but all sorts of people are bringing all sorts of poorly chosen and trained animals into the arena and there are considerations that affect public safety quite severely...spread of MRSA etc..fleas...all sorts of things..