I played an outdoor show in a really big park a few weeks ago. There were lots of bands, lots of genres, lots of age groups. Some were incredibly experienced, some were newbies. I saw lots of different amps, and I'm sure every bass player had his own incredibly different thing going on. The sound in the park was absolutely amazing. For all the bands. Many of the musicians were commenting, others just there to see the show were commenting also. I mean, the guy doing sound really knew his game.
So, my point. The soundguy seemed incredibly relaxed, wasn't getting upset with anyone (despite a few instances where it may have been warranted), and wasn't giving any direction to the bands other than a volume tweak here and there.
You can twist, turn, and defend this however you like, but a truly good soundperson's job is to take what they get, and make it work. Not to go passing judgements on musicians and their preferences. A bass player might have very good reason to be EQed in a way that you just can't understand. If he and the rest of the band are comfortable with that, if you're going to do a good job, then it's your responsibility to make it work. And I'm certain that this can be done, I've seen it countless times. If you can't accept that as your responsibility then I can only guess that regardless of how many years and how much experience you have doign this, you're going to do a crappy job, or be miserable doing it because the majority of people aren't going to comply with your wishes.
Not sure what all of the "I'm not talking bar scene" is about either. Seems you're making assumptios or judgements here, but I don't know.
Again, I've worked with countless sound people, "and I'm not talking the bar scene", and the ones that did the best jobs and worked in the biggest places were the ones who pretty much kept their opinions to themselves, talked to us only about volume, and compensated for anything we might be missing because of that in our individual monitors.
Perhaps I get defensive about this because it always seems IME that the soundpeople who talk the most, talk the most about DBs, frequencies, and what others are doing wrong, typically do the worst job.

Or I had to much coffee today, and the last time I posted in this thread.