I was just reading the rehearsal notes from last night and, yeah, sometimes it bugs me that I don't know all these theater references (and pop culture references). I've never seen a show on Broadway (or the West End) -- heck, I've only seen a show at the Curran once or twice. I don't follow the Oscars, or the careers of famous actors or designers. I don't have the slightest what is being written today, unless I happen to get hired to work it.
And sure, some of that is just not being that interested. But it is also that there are only so many career-related hours in the day. To work technical theater, I have to spend at least an hour every day studying the ever-evolving technology map, plus constantly improving my understanding of acoustics, psycho-acoustics, music theory, electronics, information theory, etc., etc.
But the divide is of course more basic. You could see it back in high school; the techies would be the small group in the back of the cast party, still wearing crew blacks and not talking to anyone else.
Actors are generally in for a longer haul but with a smaller time commitment per interval. This means they need to be networking through the rehearsal process (and can often take on multiple simultaneous commitments). Techs and designers are on for a shorter haul with longer days. Every hour spent in tech rehearsal is a second hour of work that needs to be done before opening. For me, at least, that means I don't network during a job, or do anything other than work and sleep (and not a lot of the later, either).
Which is a good fit to what seems the archetypal character; actors are social, egregious, popular -- and they know the mainstream culture well. Techies are loners, outcasts, and geeks -- and what they know is technology.
The Venn diagram has intersect, but between the norm of each group there is no meeting of minds.