Yeah, but them very same type of folks (like where I grew up in "rancher territory") who can't (or won't) regularly spend on "woowoo crap" will happily budget a reasonable monthly (or even weekly) fee for a bit of good advice, some stretching exercises and "adjustments", and a bit of basic applied physical therapy techniques that provide a measure of genuine relief. That's how chiropracters in "farm country" make their money.
They basically are as you say "practicing physical therapy" (and some other similar and related services) under a different license (chiropractic). If they didn't provide a valid service in places like that, they'd be outta business downright quick-like, because them small-ish towns, word gets around pretty quick if you done somethin' bad like scammin' a hard-workin' neighbor with "woowoo crap".