Just as a matter of passing along trivia, I seem to recall that the old standard width of 7.5 feet had to do with some States having laws prohibiting a wider trailer on their roads, Interstates excepted. I suspect that the few holdouts have now seen the error of their ways.
Happy Camping! ///// Richard D.
2006 4x4 Ford 250 SD / 2007 Flagstaff 827 FLS
One very patient wife and one furry child who travels with us. Forty-two years of trailering and camping, and I still have a blast.