Mixing boards have volume faders for a reason: any competent sound engineer is going to set the preamp input level on the channel correctly before raising the fader and sending signal to the FOH speakers.
Live sound engineers have to deal with keyboard and playback DI signals all the time, which are just as dynamic and full range as a bass pedal and in some cases much more so.
A "sound engineer" fearful that a DI signal is so potentially dangerous to their PA that they won't even set the input gain properly and listen to the signal has no idea what they're doing.
Or they just don't have time to mess with a piece of gear that's unfamiliar to them, or have had tacos break things in the past. So as a policy, and since bass works best straight into the board anyway, they just bypass all that crap and get on with the rest of the job.

