That's gonna be me
Professionally, I'm a dev but skill-wise, I'm both, dev and "audio guy", as I started both even before elementary school. I think, those are the greatest passions in my life. Well, that's a lie. There are just too many things for a top list... There is gaming, writing, game design, etc. Too much to do, too little time, you know the drill
Anyway, to get to your question:
Personally I do use fmod. Not for the sake of not having to program but rather because the tool itself is so very powerful. I use it for adaptive music and for dynamic sound effects controlled by the game (like engine sounds, weather transitions and so forth). It does have some flaws, though. For example, you can't spawn oneshots at random locations in 3d space. Still, very powerful.
You got a point there, however, regarding the avoidance. It is true that you don't want to get ripped out of the process when doing your audio stuff every time, having to switch back and forth between tools and even mental states. I like testing out my stuff in fmod first, tweaking all the nobs until I'm happy before I start implementing. You can then simply send parameters from Unity (in my case) to manipulate what you've already tested in fmod. That's very smooth work flow in my opinion.
I do, however, love to program. So that's nothing to do with it, no struggle whatsoever. I just prefer to concentrate on one thing at a time.