I'd say probably a lot depending on just how much they move the containers around. For an off the cuff calculation considering just the wear from containers we can take the support pads as being 6 inches (larger than real life) there's ~78 pad lengths between it and the far end pad that are untouched in an unmoving stack and if we move it sideways as well there's ~14 so that's just shy of 1100 spots each pad could rest that aren't used under a static container stack. This does ignore the wear from the tires of the movers but it's a quick illustration of all the space underneath the containers that can be wasted.