There would be some.

Have you considered a Pignose or Mini-Marshal? If you wear it discretely would they notice? One per performer, top up the batteries as you drive there.

Martin Brinsford (Brass Monkey, and various ceilidh bands etc) is an Harmonica player and in sessions he has to use a Pignose to compete, I would assume his style benefits from less aggressive playing which is not as loud. He is well respected as a drummer and harp player (and drum with harmonica player!). It is all about respect for the music IMNSHO.
You couldn't do justice to "the Unquiet Grave" at 100 decibels.