Well lets see ST tires seem to cost less than LT tires, and are designed to run only on trailers. They are designed to roll along in a straight line 99.999% of the time, only take the high side loads when doing a sharp turn into or out a camping pad.
Big rigs use the same tires in all positions, steer, drivers and trailer. Most will take a set of steer tire casings (different tread pattern) and have them recapped then use those on either a trailer or as a set of drivers. Think of the forces on a set of tandem drivers! I have LTs because I believe they are a better stronger tire.