Potentially dangerous mistake in March RV Magazine

It's ironic that I always chock my trailer before un-hitching yet none of the trailers at my dealership are ever chocked and none have rolled away (and our yard is not level) even in the severe summer storms. When I'm parking trailers for our RV show at the fairgrounds sometimes the tongue will swing a few inches but that's because the axles are under tension otherwise they stay chockless where I park them.