If you're 12 years old and it's the family computer (which I suspect was a not-insignificant part of the target market), you've also got to negotiate opening it up and sticking in a circuit board, adding drivers (and thus becoming prime suspect in every subsequent Windows crash), and finding some way of actually vibrating the air, which at the very least involves buying desk speakers and negotiating space on a desk which might not be your own.

Also you don't have $100.