Ugh. Wear earplugs if it's too loud. Simple as that. FWIW there ARE genres around now using massive volume with the intent of creating a physical element to the live show that is well beyond most other bands. Stoner rock, doom, drone, all these kind of bands are for the most part all about high volume for this reason. This idea that a band has any responsibility for their fans hearing health is absurd. No one is forcing anyone to stay in a room/not wear earplugs or go see a loud band in general. A friend of mine likened seeing my band to getting a full body massage for an hour. That's the point of it for us at least. Of course, some just plain like it loud and could care less about the physical element it brings. That's fine too IMO. Last show we played, the other bands on the bill we're great and all, but the soundguy had them so quiet on stage and in the PA that all you could hear is people talking over them. We tell them just mic the drums and the bass will come from the stage and it was way louder than all the other bands and the PA. Not everyone is playing music for people to chit chat over and too many soundguys try to force some lame-ass minimum volume level on every band so they all end up sounding the same. It sucks. Just let bands put on the show they want to.
When I saw the band Sunn play a couple years ago, I made the mistake of not wearing earplugs. They play around 120-125 db's on stage, with PA support for subs/vocals/keys equally as loud. Inside a 400-500 person capacity bar/venue. For an hour and a half the whole building was shaking, I could feel pressure on my chest and my eyeballs would shake against my eyelids when I closed my eyes. Absolutely the most intense thing I've ever experienced. It was great. It was also no one's fault but my own that my hearing was messed up from that show.
/counter rant