For people without major stereos or electronics, what is the major purpose of having one? Couldnt it overload the system?

for somebody without any high drain electronics and just stock audio system, and not much aftermarket electronics the OEM alternator is fine, and WILL NOT overload the system, just have extra amps if you where to have something of high current drain running when the engine is too. If you have an aftermarket audio system with amplifiers then usually the use of a 100watt [or higher] alternator is required for other devices to operate properly.

Personally, A high wattage alternator couldn't hurt your car, just your wallet, and would be poor decision for someone with only OEM electronics and a required purchase for higher end aftermarket audio systems.

-justin

The alternator (high current or oem) is the source of power (paralleled with battery)and will not overload the system. The alternator is what gets overloaded if continuous heavy loading on electrical system.