A gasoline motor has to reach a certain RPM to achieve it's maximum torque. The 5.0 Liter Mustang wasn't a popular car because you had to wait for the power to kick in. Not only is acceleration on an electric kart so much harder, the electric kart can drive much more like a car. Our karts even have three electrical keys that alter the accelerator signal to limit the top speed to a level that is appropriate for the driver. A key can be swapped in seconds.
Parents choose which keys the driver has.
An electric kart has the capacity to have a reverse circuit added in. An electric motor runs backwards, too. I haven't seen any gas go kart motors that run backwards. The electric karts don't have any dangerous, potentially explosive fuel that has to be handled. The batteries are sealed so there is no hydrogen present and the batteries can't leak unless physically punctured.