If your value system was the masses value system, nobody would buy a new Hyundai Elantra for $15,000 because they can get a used one for $3,000. Yet, the roads of full of new Elantras, Sonatas, Accords, Mercedes etc. You are trying to whittle down capitalism to such a low level that there is an implication why buy anything new...a *new* item is considered luxury as long as their is something less expensive that will satisfy the requirement. Life just does not work that way.
What you said makes no sense. Everybody who buys a new car buys it because they WANT a new car not because they NEED a new car. Most consumers do not buy goods based solely on their needs, they also factor in their 'wants'. Hence these new cars gets sold.
Back to the point, a Moto E is what is NEEDED by most consumers for a phone. But consumers have WANTS such as better camera, better design, etc". This results in them buying more expensive devices than the cheaper alternatives. I have seen older folks who does nothing on their phone except call and text. They don't know how to send emails or even take a picture.
If I am filthy rich I would very well want a 300,000 car and probably purchase one (I want a Lexus LFA). But I would not say it is a necessity.