Agree with your statement as if you are using money then more money will come to you. The wealthy people are wealthy because they create new way of earning through utilising their own money. Poor people think that if they spend their earning and reward then there will be nothing with them to buy expensive things but they forget that desires can be achieved anytime but once you spend money in useless activities then you will not able to increase your cash.
Sometimes they think that investment is a waste of time but they don't remember that with this investment you can avoid harsh situations, your life will not be burden for you.
May be they are not investing as they wants the happiness of their family to feed them in restaurant and to give them expensive cloths but they can also invest money because after some patience they will be able to give more comfort than this if they wisely invest in wise coin as it will offer them passive income.
Rich people earn more money by using their asssets not money. Your fiat currency is useless as it is losing its PPP power every second. So as long as you are holding your paper cash and not buying any asset like bitcoin, gold, land with it you are not utilizing it.
Poor people don't think investment is a waste of time and they know that rich people increase their wealth by investing money. They don't want to invest their money because they think that if their investment turns negative they will lose their small money as well. Their lack of knowledge about money management let their fear dominate them.