Use diplomacy whenever you can. The entertainment business is like that. Keep the griping and grousing behind closed doors whenever possible, and task your most cordial, agreeable person with dealing with the a**holes that run rampant in the business. Keep in mind that as long as the sound is just only adequate, a stellar performance will win the audience, who generally doesn't spend much time over-internalizing live sound reinforcement issues.
I'm guilty of not following my own advice, mind you, and can attest to the fact that it does you no favors to put up a stink if you plan on playing the gig and/or returning to the venue for future engagements. Yes, it can suck dealing with grumpy, jerky provided help. Up to the point you are blatantly being disrespected (that's an altogether different topic) - and I don't think this rises to that level - you'll find that being cooperative will benefit you in the long haul more than not.
Or, just don't do the gig.
JMHO.
I'm guilty of not following my own advice, mind you, and can attest to the fact that it does you no favors to put up a stink if you plan on playing the gig and/or returning to the venue for future engagements. Yes, it can suck dealing with grumpy, jerky provided help. Up to the point you are blatantly being disrespected (that's an altogether different topic) - and I don't think this rises to that level - you'll find that being cooperative will benefit you in the long haul more than not.
Or, just don't do the gig.
JMHO.