It's not just the weight that's important, whether that weight is spread out or focused in one area makes a huge difference as well. Sixteen wheelers are designed to spread the weight over a larger surface area specifically to avoid damaging the road. It's literally the reason they have so many wheels.
On the other hand, if you look at the cracks that Jasmine left behind, it's not her entire foot that's causing them. It's when she shifts her weight toward the front of the foot to take a step, when all of the weight is focused in a smaller area.
Of course, just dropping her sandal also seems to have been enough to cause cracks, so maybe it's just a really shitty road.