How do you feel about emotional support animals on flights?

I hadn’t noticed this much before but in LA the other week I saw a couple of comfort dogs – apparently you can take any animal on a plane provided it’s for emotional support. Whilst dogs and cats seem to be commonplace I read somewhere that the animals people take can be quite exotic – like a small horse.

I’m not sure about the practicalities – who cleans up after them when the seatbelt sign is on? How do you seatbelt an animal? What about the stress caused to the animal from decompression?