SNIP ...
I think that Tim has it - these things are down to personal preference, but, like you I really deeply resent the idea that you can't be a 'real' photographer if you don't do it 'properly'. In fact, I suffer from this all the time from 'real' landscape photographers who don't believe that you can take 'proper' landscape photographs without MF and a tripod. We all have to make compromises - otherwise everybody would be using 10x8 cameras!
all the best
Tom,
My wife conducts the Victoria Civic Chorus and because she sleeps with me, gave birth to our twins, doesn't give a hoot how much I spend on camera gear, and is the perfect wife, I photograph her concerts for her. (I know I know, did she get the short stick on this deal or what :ROTFL
Anyway her concerts are either in a church or auditorium with mixed sources of light and the chorus singers are all dressed in black! With the M8 (and I assume with the M9 too,) I have to use IR cut filters at these concerts because tweaking each keeper takes far too much time (and frankly, my correction profiles "ain't that good".) So I have either a Leica or B&W cut filter for each lens. My point is there are reasons to keep those cut filters handy if you are shooting under conditions that will produce lots of magenta cast.
In my morning walks with my dog I try to stay away from filters because - as has been pointed out earlier - filters will cause light reflections. BUT, those light reflections are much easier to correct so if I forget to take the filter off, no big deal.