Doctors and different drugs/treatments, Contractors and brands of power tools.
Programmers do seem to make the biggest deal about "all the fighting", everyone else seems to just accept that professionals are opinionated and arguing is how progress is made. But I'm on the inside with the programming stuff and on the outside looking in for the rest of these fields so maybe that's not true.
From what I've seen, smart Doctors and Contractors eventually get to discussing empirical data and costs. Far too often, I've seen programmers just make up crap and state it emphatically.
I actually built in anonymous usage logging into TermKit using Google Analytics over SSL. It logs the types of commands you execute (no data). It's my plan to release this data back to the community regularly. I don't think anyone has done a large-scale survey of command-line unix usage before. Should be interesting.
Edit: and you can easily turn it off if you wish.
I think the culture would be a vital part of an ecosystem of empirical observation. For the sciences generally, the culture predated the sources and gave rise to them. For medicine, I think a culture of empiricism was imported from other scientific fields. For contractors, they are very motivated to note what works, what breaks, and what enables them to make more money.