For some reason people equate this to me shoving it down their throats. There was a big reddit thread about it recently.
I don't know about "strong opinions in both directions" (I don't think I've ever met someone who felt strongly that an academic doctorate title should never be mentioned?) but there are certainly some people who are serious about "ring-knocking" and will get super offended if you don't say it, and given the 'do whatever' instruction, people may be defaulting to putting it in, just in case. Perhaps, again, not even out of fear you'll jump on them, as much as someone else might.
In other words, it might not be you so much as the other assholes.
Your actual person I of course know nothing about and pass neither judgement nor praise for. That is none of my business!