His dog has a distinctive handle that's only ever seen on guidedogs for the blind - that handle isn't used for other service dogs.
ouch.
Doesn't surprise me at all to see that today's super individualistic people didn't think twice about minding their own business when they see what appears to be just a guy with his dog. For all they know it's just a therapy animal, because he doesn't -look- blind.
They give you a piece of paper that says "service dog", that doesn't make it a service dog in the legal sense.
And yet, they (probably) make no false claims so they are not breaking the law.
The Washington Post actually just wrote this up:
https://www.washingtonpost.com/news/tripping/wp/2016/12/27/w...
> To further complicate matters, it can be difficult for staff members to identify a true service dog. Although pet owners can easily buy unofficial documents or apparel, these papers and emblems have no bearing on ADA compliance: The law does not allow public accommodations to require certificates, licenses or other physical proof that a dog qualifies as a service animal. Yet the ADA does not permit questioning a person about the nature of his or her disability.
The general issue is that it's a much less big deal to let a scammer through than to accidently hassle someone with a legitimate service animal (big fine!).