I am assuming that your tires are 8x19.5R (i.e., 19.5-inch tires on Alcoa rims). I say this based on my having had a '94 LY 34-ft diesel pusher. When I had new tires installed, they put the sand bags into them. These sand bags burst open and disperse the sand to smooth out the ride - i.e., they dynamically balance the wheels. Tire pressure is also very important, and you should follow the recommended pressures (mine had been 90 lbs in the rear and 80 lbs in the front). Using a TPMS (tire pressure monitoring system) is highly recommended - I had the experience of having an inside rear tire blow out and it tore part of the bottom side of the motorhome. As well, you need to know that your tires are less than 5 years old from the date of manufacture stamped on them.
No, you are NOT paranoid. Your safety depends on those small patches of contact between the roadway and the vehicle provided by the tires.
1987 Excella 32-foot
1999 Dodge Ram 2500HD Diesel