I can't stand the mixing at many concerts unless I wear earpro, but thanks for the reminder.
I'd rather not go at all at that point. Why bother going to a musical performance when you are just going to muffle the sound.
As an middle-aged man that loves to go to concerts, ear plugs are great and do not affect negatively the concert-going experience. Speakers are loud enough that you can feel the music and personally I get energized when people around me are enjoying the concert with me. Plus, your ears will thank you later :).
See "concert earplugs" that try to reduce the volume with minimal distortion.