Amazing Race, are they excluding people who can compete with disabilities?

Why on the show The Amazing Race they always seem to have the obligatory Gay couple or person which to me seems like the token Gay but don’t seem to be that adamant about having a ubiquitous representation of people with a disability or handicap like legal blindness, deaf, Little People, or maybe someone with a prosthetic etc? It is like because they don’t have as much visibility or something that they are not thought to be included in every series like Gays. Have you noticed that?