Both rich and poor save for the future, but the question is who saves more and who invest?
Poverty isn't a licence not to invest, it is said that a wise man saves so he don't get bankrupt when in need, nevertheless a wise man should invest too be you rich or poor, there are risk in investment, but not when you invest in the right place with the right income.
Nevertheless that's a story a poor man doesn't want to listen to, because the little he cuts his meal to get a reserve for the future shouldn't be put at risk of not having anything in the future if the investment goes the wrong way, but a man who has money, who is rich I mean, will invest because he believes he is doing the right thing for the future, when he puts this he will get a double or triple of that, and that's far better than keeping it to come get it in the future with no interest.
That reminds me of the servants in the Bible who were given talents, some made use if theirs wisely to invest in business that will give them their capital and profit, while one buried his just with the hope of do it out when the master asks of it. The servants were SERVANTS indeed that means they weren't rich, they needed money yet they invested.
So I think it is wise to invest honestly whether poor or rich, to get greater than just what you saved for the future.