Cheezus, I didn't realize there had been any further responses...my apologies.
They are far from Amish - no beards
Maybe recent deconverties? 
Or victims of
Sam Mullet maybe

What you saw were likely Mennonites or Beachy Amish. They are kind of like "reformed Jewish" of the Amish world. They may own vehicles, but the vehicles are generally for work use and are to be strictly perfunctory...no flashy trim. AFAIK, the order of Amish, in rank of conservativism is; (1)Old Order Amish (2) New Order Amish (3) Beachy Amish-Mennonite (4)Mennonite.
Thank you for that lil tid bit. Makes perfect sense seeing that the two fellows were hauling livestock. The woman may or may not have been an employee of a historical museum of sorts.
How would you like to be the next in line. 
Took me a full minute to figure out what you were talking about and I must say that being next in that line would put me off my lunch

Best of luck to you in you're travels, Mr. Blackwell!!!
And to you as well! My brother has been doing this for about 10 years now. He will become an owner/operator next month and we have discussed driving tandem. You will definitely see some great stuff.
First time I saw the Rocky Mountain range was a spiritual moment for me. It looked like a tidal wave washing over the plains. Bryson, MO is a neat little town and the Ozarks are beautiful as well.
One of the other mind blowing things I see from time to time is wind turbine blades and tower sections being hauled down the road. Seriously, those blades are huge and hauled in one piece. Your average trailer is what...53 ft? The blades I've seen rolling down the road and pulling into truck stops are about 3x the length of your average tractor trailer.
see here
Also, hope you have nerves of steel and low levels of road rage because there is a whole plethora of assholes and idiots driving our great interstates...and, the construction...never...stops.
I am currently sitting in a rest stop somewhere near Lebanon, IN off of I-65 south bound heading towards Panama City, FL. From there I will be heading to North Carolina and stopping off at the house for my youngest daughters second birthday.
P.S.
If I have to rewire and patch up my pig tail one more time I'm gonna have to just shoot somebody.