You obviously missed the point.
It's the RC car. Why did Hasbro make something that was never meant to fit in the MLP world? This is probably the most messed-up toy they made.
considering flim and flam made a magic-powered automobile, it's not that far of a stretch.
it's not about show-accuracy when it comes to toys (for Hasbro at least). it's about selling merchandise.
who knows, perhaps some rich pony will have a car-like vehicle in season three