The reason money is important when one is old is because by that time you won't have the energy of chasing money and when one is old you can fall sick at anytime and in a situation like this money is needed to go for treatment. Old age you need to eat good food to nourish yourself well to be strong. When one is young you decide to eat junks and still be okay but at age you can't eat food like this because it going to affect the health
Getting old doesn't mean to have no energy to collect money. There are many old people who have more energy to collect money. We must remember that collecting money won't be always with physical activities, but we can collect money with our intelligence. Be the owner of a shop is one of the ways to collect money. When you are an old person, you probably prefers to lower your physical activities. For the physical activities, we can hire young people.
However, to have a shop or run a certain business, it requires money. Saving is one of the source to get enough money for running a business. But smart people won't rely on the saving only, he must also try to have investments. Saving may be a source of reserved money, meanwhile investments for growing our money in the future.