It actually is, it's just not from the ADA:
https://www.dva.wa.gov/counseling/service-and-companion-anim...> The U.S. Department of Housing and Urban Development (HUD) is a federal agency that administers the Fair Housing Act (FHA). Under the FHA, a service animal is defined as an animal that is a necessary reasonable accommodation for a person with a disability. Emotional support animals and comfort animals ARE included in the HUD definition and are therefore allowed into a person's dwelling.
> There should be no "pet fee" for the service animal. The person with the disability must request the animal as a reasonable accommodation for the disability, and must be able to show that the animal is necessary because of the person's disability.
Basically it's using a more expansive definition of "service animal" than is typical, such that just about anyone could probably get their pets to qualify if they want.