Honestly i believe that as long as a band is relatively educated and knows what they want you should give them only that and not what you think is better. That is yours job. If something can not be done then you need to spend the time to explain why can't it be done. If you are touring with a band of course. When you are working in clubs or festivals with multiple small bands this is almost impossible.
The other thing is, i don't think you realise up to which extend the room i'm working in is acousticaly terrible. This is one of those places where you are happy if all instruments can be recognized withouth getting yours head chopped of. You don't bother with the small detalis like colour of the mix, you fight with getting everything out without drowning everything else.
Things like all guitars having a side chanied compressor triggered by the vocal so you can hear the vocal at all are normal here.
Guy is cupping the mic, this is the second time he is on stage. You are running 3 bearely working yamaha monitors and can't give him any stage level. The room is a huge concrete basement that can fit 900ppl, you only have 80 on the concert. There is more reverb then in a 4km tunnel. You have very little gain before feedback. You had to ring out the monitors AND the PA because od this. You don't bother with details here.
When i'm doing parties i try as much as i can to try and get the song as close as possible to what it sounds like on a pair of monitors but this is not really very possible. You can't get a yamaha club series system at a 110dB in a more the half-empty huge concrete basement to be comfortable for listening unless you dich 1-5k area for even up to -5dB in the worst spots.
Of course, this depends on the music itself, sometimes you have minimal techno with very little elements up there so you don't have to do this.
And the amount of people + humidity + temperature affects this a lot. So i do changes during the party all the time.