Although this may be the case with you, my experiences(although admittedly limited) is otherwise. Most soundmen don`t know my tone. In fact, many of them think the proper bass tone is the sound coming from the kick drum and with the bass DI`d to almost inaudible levels.
Like others have said, this is because many novice soundmen are subject to mainstream music and don`t understand a proper mix for a rock band with a bassist who actually plays something other than 8th note roots the entire time. Soundmen need to trust that I`m not trying to steal the show and that I actually do provide very important nuances to my bands sound. IME, it`s either ignorance or laziness from the soundman that cause most bassists concerns and/or complaints.
Unfortunately, if you listen to the music that some of these junior sound guys listen to (part of the era they were brought up in), I can see that they would have a hard time extrapolating a real mix out of what they have been conditioned to hearing through their I-Pods.
You can probably tell that I'm just a little bit more old school than that. I cut my teeth mixing acoustic music 30 years ago, folk, jazz and rock mostly but a lot of international music too. I am not comfortable mixing much of the new music, where to me anyway, I have a hard time decyphering what's really going on within the din and rumble.
Funny story, every year or two I work with Kris Kristofferson, and when he first came through town he took a look at the lighting guy, my monitor guy and me and kind of rolled his eyes saying that at least we held promise. So during sound check, we get him up and running and the first time he heard his guitar he got this big grin on his face. We get things all dialed in, he's good and then go off to dinner break. Normally Kris doesn't do all that much singing during his live shows, and kind of keeps to himself. Tells a lot of stories and it's a fun show. About half way through the show he starts playing stuff that isn't on the set list. We follow along of course and the show keeps going on and on, the audience is loving it, Kris is singing most songs and there's tunes not even on the set list. He does like 35 songs and we have no idea what's next or where we are. Finally, he says over the PA that he knew the crew at the venue had promise because they were older, respectful and made really good choices during set-up and sound check. He said that was refreshing to encounter this on the road and that he hoped the audience appreciated our effort and professionalism. He also appologized for going on so long, he was having too much fun to quiut.
That's what we as sound professionals strive for. Those were some very expensive tickets IMO, $70-$100, and all 1000 audience members left that show feeling they got more than their money's worth. Now when he comes through, he knows he's going to have a good time and really loosens up, and the shows sell out too.