In fact, it's not unusual that the entire earnings of a work-life of a mid-class worker do not add up to something that would make a person rich, even if 100% of it is saved.
The other side of the coin is that mid-class life is pretty good, most of the GP advice will lead to poverty much more often that it'll lead to wealth, and the one important piece that is "create more" comes by responsible working.
Having fun and playing ("irresponsibly"), expressing your true essence, is the only way to create ANY lasting value.
It is also the only way to create any wealth. The OTHER (much more common) way that people get wealthy is by capitalizing on what others have created. Which is fine with me (I'm all for the wonders of capitalism), but I prefer creating my own wealth.
Most people get bored, and will only create something for themselves if they act responsibly after a while. Unless what you call "responsible" is working for other people, instead of the more usual "hey, I don't want to do this right now, but I'm doing because I know it's good for me" meaning.
Also, to say those people aren't creating wealth is very offensive.
They get richer than they would by spending them.