Who paid for the great works of music in the period between 1700 and 1918? From such musicians as Liszt, Beethoven, Mozart, Bartok, Handel, Debussy, Bach etc... there were a heck of a lot of great composers in that period. I was analyzing Bach the other day. His Brandenburg Concerto #2 has tens of thousands of notes. That is a heck of a lot of work.
Patronage. Honestly music was profitable for a very brief period of time between around 1940s-1990's. Every other time in history it's required someone rich to like you enough to pay you to do it, or be a traveling minstrel who lived on the edge of society. Like even Wagner who is arguably one of the most influential and popular composers of all time spent most of his life destitute and only was stable when the Kaise…
And some of them earned less then they could due to own habit of alienate people (Beethoven).