You might look at the above and think it's just a cute novelty shape for a remote control car. You would be wrong, and reckoning without the way a Japanese inventor thinks.
First of all, it helps to know that some Japanese public toilets look exactly like that, sans wheels - just a porcelain thing in the ground that you squat over.
Secondly, watching this video makes the intent abundantly clear. You're supposed to use this to trick people into shitting on the ground by faking them out with it and then driving it away at the last minute.
Alternately, you can use it to deliver drinks, because, yum!
Nice of the image to tell us it can handle a 400g load. Not that I've ever weighed any of mine, but that may just be hidebound western thinking.