To answer the OP: I absolutely agree.
And as far as any audience is concerned, this is how I see things:
Once I'm playing for an audience, I need to at least somewhat "deliver" what is being asked for.
When playing original material, it's possibly somewhat less important, but in case I don't care at all I need to be prepared to not play for any audiences pretty soon anymore.
When being paid, it's absolutely obvious that I have to care what the person hiring me (and/or the audience) wants, otherwise I won't be playing paid gigs anymore.
So much about certain prerequisites.
Part of that "delivering for the audience" is to present yourself well. This includes playing as good as you can within the realm of what you were asked to play - it obviously doesn't make much sense to fire off your chuggachugga riffs over "Tea For Two". And talking about the latter, I found it to be a very wise idea to take these songs every bit as serious as any wicked fusion gig, even if you might at first think that this stuff is way below your level or simply not demanding enough of you as a proficient player.
Now, playing as good as you can is as well related to sound. You will only deliver your best performance in case you have the best possible sound (of course the general conditions need to be considered, there's just no way to bring a fullstack for a hotel lobby bar jazz gig, even in case it might be the best sound).
None of these are anything the audience will directly notice. Your playing should always deliver enough headroom and your sound should always at least exceed some minimal requirements.
And yet, of course the audience will notice - because of the entire package. Which is even more true when you're playing with a band. Your bandmates may notice you're not playing as good as possible. They may as well notice you're not sounding as good as possible. And last but certainly not least, *you* will notice both. And it'll annoy your bandmates and yourself. Then let's assume your bandmates are doing it the same. You will then see them not caring at all and as a result, you won't feel inspired to do it differently. There's your downward spiral.
A lowest common denominator strategy has never been proven to be a great thing.
Then add this: What if there's some "important" folks in the audience? Maybe some with more musical understanding. Maybe the guys who would like to hire a band one day in the future. What are the odds they will hire a band doing it "so it barely works", especially in this tough market when you can find bands playing their asses off regardless of the environment?
Bottomline: Play each and every gig as if it was important.
And well, I know about all this quite a bit because I had to learn it the hard way myself.
