Yes as long as they know how to handle their money well and wouldn't overspend.
I think the problem why salary earners aren't being successful is due to how they handle their earnings most of them spend too much on drinks or gambling as for their reason is to relax for their hard work and because they've earned it.
Many of us use our earnings to buy something that we do not really need to save that money for our future. Besides that, sometimes we have to face an urgent situation that forces us to use our savings to cover and solve the problem. But I believe that if we can still save every penny we have, we can be rich in the future, as long as we keep trying hard from what we did.