> Musicians may listen to music at higher levels in order to hear the more nuanced musical aspects or may simply enjoy music more so than non-musicians and are therefore happy to listen to music at a higher sound level.

Makes sense. Many non-musicians just want the music loud enough so they can hear the lyrics. Musicians are interested in hearing the whole band. I don't necessarily want music to sound like a live concert or shake my body, but I do want to hear everything clearly.