Simply put, if there are only three bands playing and we are the headline band and are ordered to turn up several hours before a gig for a soundcheck, I would expect a bit better than just a DI box awaiting me! Playing in a three piece band most of the time with bass, drums and guitar, its not like our set ups require the soundguy to spend ages with a horn section, keyboards or other stuff.
I don't run an extreme setting or anything but the fear of the DI box puts me off using a passive bass at gigs, as a bad soundman can completely change the character of the sound of the bass in a bad way. I don't buy the 'what sounds good to you may sound crap out front' as a reason for always using a DI box, as it kind of gives the impression that the bassist in question has no real idea on how to use eq. A crappy thin, middy P bass tone is going to sound pretty weak regardless of the system its being played through. Of course some bassists really don't know how to use eq, and some soundguys can make a passive bass sound amazing from just a DI box.
I also just don't buy the 'he/she is protecting himself/herself in case your amp goes', half of the time it is just lazyness and at most gigs, there is about as much chance as the PA 'going' or their Behringer DI breaking down as there is of my amp.
With that said I never really kick up a fuss and even understand using a DI box if there are a lot of bands playing at a gig (for me this is more than three), with lots of different amps and no soundcheck for anybody. Usually if a soundguy gives me a good reason why he is only using a DI box(small venue, very little bass going through PA anyway, time schedule etc) I will leave him be and just use the box, as life is too short to get wound up about such things. But if the answer is just because he can't be bothered, I just make sure to take the Sansamp out of the gigbag.
Rant over! With all that said, most sound guys/girls I deal with range from good to excellent and are very easy to deal with. My rant is just based on the few times that I have just been at one of 'those' gigs.