As an original "redneck" or "hillbilly", I have to say that yes, your conclusion of trucks & the hillbilly drivers attitude are pretty close...well right on. But I do have to defend them on a stand of ignorance. Hillbilly's are NOT cyclists, and have ABSOLUTELY NO IDEA what cycling is about. They ride animals that are usually in excess of 1,000 lbs. & usually flailing through the air for 8 seconds at a time. Not that I think they should "side swipe" cyclists, but I do understand where they're coming from, both mentally and physically. And I apologize on the bad behavior you've experienced. I wouldn't want any fellow cyclist hurt for any reason! Take care!
T.C.