I've never been shown how to change the oil of my vehicle. All I know is that it needs to be changed every so often, and rather than risk ****ing up my means of transport, I leave it to professionals for a nominal fee. They also tell me when I need air in my tires, certain fluids and whatever else.
As long as these places are owned by a corporation that only cares about its profit I can't believe things will changem not until these hourly workers don't have quotas to fill and threats of losing their job over their heads. I can hear it now: "I see you haven't sold any transmission flushes this month...we need to have a talk."