I do earn a living wage from freelancing. Simply put, it is a business that takes work because you are your own boss and are responsible for all aspects of business.
A full time freelancers survival rests completely on their shoulders and is no different than if they were to open a local brick and mortar business.
Actually, freelancing offers you a huge reduction in overhead costs because you don't have to work out of a traditional office space. Here in the USA quality office space can cost upwards of 23 dollars a foot, not including heat, light, phone, insurance and more.
Freelancing allows many to keep their day jobs while earn what I call fun money. How much fun money a person wants is relegated to how hard they want to work.