I'm the same -- when it happened in Broen, I was completely nonplussed (btw, what was that with the wig? Did any of you who watched the original get that?), just because it seemed so unlike M.
SPOILER:
Then again, without those scenes, the main villain's motivation would be even more obscure and hard to believe than I already thought it was, so. Though they might be going another direction with the FX version, so who knows.
I also feel maybe it's just to let us see in how many ways his home life isn't going that well, either -- btw, I felt that the issues with his son are given much more screentime in the original than in the remake so far; does anyone else share that impression?