yeah, the VESC firmware has traction control settings, so each speed controller is talking to the others and has a maximum allowed speed range between the wheels, which might help for sand? trying to accelerate on wet grass, there was a bit of slip, but you could hear the motors all micro adjusting their speed, and eventually you would get moving enough that they all went back to full power. sand might be a bit harder because the wheels + weight would want to dig into the sand.

but yeah, it was pretty nice - when i went to the general store to get ice, the people working there were unloading ice from a truck up on the street, and walking it down in plastic bins (probably a 2 or 3 minute walk from their van). They looked at the cooler kart with envy haha - so i could see some applications for it, but they are all fairly niche, and less transportation focused i suppose