Best guess is that it's disabled for anything but track/trick stuff. There will be some cool videos eventually showing up with tricks people pull with this. I don't know what else it's for.

I can imagine the lateral thrusters helping it turn faster on the track. Although I wonder if the extra weight is going to net out positive for lap times.

But really, a few very rich people will buy the full-rocket version to impress their friends. They'll play with them on private property.