It is no secret that prolonged exposure to loud sound is highly damaging to our hearing. Listening to loud music is one of the common factors leading to degraded hearing ability and tinnitus, and is deeply unhealthy.
At the same time, such level of noise negatively impacts the quality of sound perception, which degrades the musical side of the musical performance.
In what seems to be the echoes of the so-called "loudness war", bands still stick to the idea that "the louder you blast it - the better". But it's not true. There are many other ways to energize the crowd without causing them sound damage, and I'd love to see more of those, instead of them trying to be the loudest ever.
I'm taking live sound classes at my community college right now and we talked about this yesterday. The biggest issue with a large venue packed with people is the noise floor is very high. For instance if the crowd is 90db, then you've only got 10-20db of headroom to work with. 90db is already enough to cause hearing damage after 8 hours, and it gets exponentially worse with just a few db more, by 100 you can only safely be in that for 2 hours and that is generally the ideal loudness for that kind of venue. Of course since the engineers probably have hearing loss, they tend to raise it even higher to 110 which is loud enough to still cause damage over time even with regular earbuds unfortunately. So unless you can have a quiet crowd there is nothing you can do about needing ear protection, I recommend hanging by the engineer booth because they tend to be just far enough away to comfortably hear everything around 90db because they generally can't use earbuds while actively mixing.