I think some of us are mixing up service animals vs. emotional support animals vs. a pet. Service animals are highly trained, ADA compliant, to assist those with a disability. They are always well behaved and they allowed to be anywhere a person is allowed.
The main abuse comes from emotional support animals. These were meant to provide people to help them cope with issues, such as PTSD, or other mental states. Yet now it's being abused because the laws are very relaxed and anyone with a computer can go online and print an emotional support certificate. It crossed the line when someone brought an emotional support turkey on a Delta flight a few years. The turkey had it's own seat!! I've seen numerous people walking around the airports with their tiny dog and they bought a "service animal" vest and put it on their tiny dog Fee-Fee, while she goes to the bathroom on the floor. A real service animal won't do that. It's these people that are undermining it for people that actually need service and emotional support animals.
Then there's those with pets that need to travel with them and pay the fee that's required. They must stay in their carrier at all times and ride under the seat or be checked as an animal in the cargo hold.