Yeah, "certifications" can be purchased online for a fee, even if your dog has no training whatsoever. As a result, when you see someone with a supposed service animal, it might be specially trained to help them with a legitimate disorder. It might be an "emotional support animal" for a bullshit problem they made up. Or, it might be any random pet because the owner may be an asshole. And that majorly pisses off people such as Colin Wong, who genuinely needs his guide dog every time he leaves the house.
Colin recalls going to a department store one time with his dog, Wednesday, whom he got from Guide Dogs for the Blind, and getting attacked by another dog patrolling the aisles. Stories of guide dogs getting mauled by other dogs are disturbingly common, because of people like the owner of the dog who attacked Wednesday. That owner insisted it was normal for his "service dog" to attack other dogs all the time. "It's clearly not your service dog!" countered Colin. "Service dogs are conditioned not to attack other dogs. That's like day one of service dog school!"
Day two is conditioning them not to set up illegal cock-fighting rings.
Unfortunately, thanks to fraud service dogs, there is some mistrust of all people with service animals, even legitimate ones. Wednesday escapes scrutiny because Colin is clearly blind, as is obvious to anyone who doesn't share his disability. But let's next introduce you to Raven Richard-Bordeau, who gets harassed all the time about Dyson, her Mexican hairless dog who accompanies her wherever he goes. Raven has clinically diagnosed depression and anxiety, and doctors recognize her need for a companion animal such as Dyson, but that doesn't stop store clerks and restaurant hostesses from constantly calling shenanigans on her. They routinely ask her to produce Dyson's certification papers. Dyson does have a certificate, but Raven doesn't carry it around on her person everywhere she goes, and you're legally not allowed to demand to see it.