Even the greatest of musicians through history have had to struggle to survive, it wasn't always about rock supergroups skipping across the world in private jets, screaming groupies ready to service their every desire.
I'm reminded of Bach's Brandenburg Concertos, which are some of the greatest works by one of the greatest musicians that ever lived. These works were not a platinum hit at the top of Billboard's charts. Heck, Bach didn't even get paid for them! These compositions were sent on spec to the mayor of Brandenburg (hence the name) in the hope of stirring up some sponsorship so Bach could continue his work.
If you're like me, you picture the hopeful rock star as struggling along, trying to supplement his income by giving guitar lessons to locals. This also describes Beethoven - he was frequently hunting for commissions to keep himself afloat, and had to earn money by giving piano lessons.
The idea that musicians should somehow be above all this stuff is a modern invention. Most of the greatest works in history were not done by people enjoying easy financial prospects.