I was wondering the same myself. I guess it's on a per-park basis and if you call the office, explain your situation, they probably all would grant an exception.
The rule is likely there to prevent 29 college students on a bus from running the place over.
2010 Coachmen Mirada 34BH, class A, 34.75' long, GVWR 22,000 lbs.
2005 Fleetwood Resort TNT 25QB, hybrid, 27.5' long, GVWR 6,600 lbs.
God bless!