Oh? Who's covered... the people with allergies, or the people who need a dog to work? I wasn't aware. Do you have any evidence for this?
Under Title III of the federal Americans with Disabilities Act (ADA) and virtually all state laws, a service animal is an animal that has been trained to perform work or tasks for the benefit of a person with a disability
In both the ADA and Section 504, a person with a disability is someone who has a physical or mental impairment that seriously limits one or more major life activities, or who is regarded as having such impairments. Asthma and allergies are usually considered disabilities under the ADAThis may be an unrealistic scenario, but it's at least an interesting hypothetical.