They pay us to play music on fairs and markets. It's nice, after so many years of performing somebody is finally paying me to do it. They demand covers, music that everybody knows and enjoys - and that's acceptable.
BUT - Six bloody hours on bass is such a hard work! I slept like a log afterwards and today I'm still sore all over.
The upside, albeit just because it appeals to my vanity, is that after 15+ years of performing I can call myself professional musician without air quotes. ;)