People always want more. They want a nice car than their neighbours, nicer phone, better clothes. We are way beyond what you need to survive, everything else is about comfort, security and status. And why is these things so important? Mate selection is based on status (among other things).

It is also typical of a famous writer and a very high status person not to see that others would want/have to compete for status in other areas. Not that she is wrong, but the world is a complex place than one can imagine.