The same issue arose, in a slightly different form, for me in Reno.
While the details vary a bit by locale, the issue all comes down to who is the "AHJ." EVERY government body (Or anyone else with the power of 'eminent domain') is their own AHJ. Railroad property, Indian smoke shops, etc. are all outside the scope of the 'usual' AHJ.
I don't see why you're surprised. These same groups - including the railroads- also have their own policing powers.
What this means as well is that every one of these groups also has the authority to require their own contractor licensing, etc. I suspect that the only reason they have not is that in most instances the "AHJ" is also the customer.
