Why we cant use any kind of 3rd party voice chat and stuff?

so i see people getting banned and stuff cause they dont use the 3rd party voice chat programms approved by riot.. I was just wondering why this happens, is it so they can make more money if people playing league only have the voice chat programm that is approved by riot? So, we either download what riot sponsors or we either get banned for using 3rd party programms. Is this how it works? :C
Report as:
Offensive Spam Harassment Incorrect Board