I know a gentleman who has been a musician and band leader for years. In his day, he used to pack the house with fans of great big band jazz.
Over the years, the economics of big band music has changed. My friend still does occasional big band shows these days, but when the door has been collected, and the musicians and roadies have been paid, he is lucky to break even.
Why does he still do it? Because he loves playing those old GlennMiller? and DukeEllington? and BillyStrayhorn? tunes.
When the circus comes to town, they call my friend to provide the orchestra. He puts together a few people and does the gig. Does he do it at cost?
Of course not. It wasn't his idea to have a circus.
He charges for that. The circus will either pay the going rate for a top-notch orchestra or they won't have a top-notch orchestra. --TimVoght