I wholeheartedly agree with your last statement, but I'd have to respectfully disagree with the rest of it.

According to Dr. Julie Helm, the last six cases of Pullorum in the US were found in 2003 - all in backyard poultry and all contracted through auction/sales/show sites. Georgia has reported cases as recently as 2002-03 and NC in 2000. As Dr. Helms says - if our neighbors have had, you can almost guarantee that it was somewhere in SC, too. The last known case of fowl typhoid was in 1987 - 29 years ago.
Makes you wonder if the decreasing incidents, and clear for over a decade now, is because of the widespread acceptance of testing by commercial, and backyard, flock owners.
I kinda look at it like rabies in dogs. There was a time when many many dogs, particularly in the south, did not survive into adulthood. But, because of widespread vaccinations, you never hear of a dog dying of rabies anymore.
While I don't doubt that there are farms that are NPIP certified flock and are not spic and span, I do know that they do impose certain fowl management, and "housekeeping" requirements.
For instance, did you know that your hatching and brooding areas must be in separate rooms, separated by a door? I didn't, until I started cleaning for my inspection. Because of the excessive dust raised by growing chicks (all those new feathers put out a ton of dust!), it is unsanitary to have them in the same room where you are incubating eggs.
I know what's it like to get behind in the work - heck, if someone came to my house right now, they'd probably declare me incompetent and put me in a home for the mentally disabled, but the goal of the NPIP and flock certification program is a worthy one.
Particularly in today's environment, even if I were not NPIP/AI clean myself, I wouldn't buy birds from someone who wasn't, unless it was someone I trusted very much.