I don't really agree with you. In my opinion the author says so about people who are in the same position as him. And in this case I also think it is true, if

I don't really agree with you. In my opinion the author says so about people who are in the same position as him. And in this case I also think it is true, if your only goal is money, then you will not spend it and waste it on anything, which will results in more money