Several years ago I was browsing the adult diaper section in a store and a lady walked up and after a few moments stated to me "you can't find your brand either, huh?" I muttered something in acknowledgement but I was actually looking more to see just what was available for disposables even though I am a training underwear / plastic underpants guy. Afterwards I wondered about her bringing up the topic so casually. I decided it was just polite conversation at the time and it actually made me feel good knowing someone else could talk about this topic without being embarrassed.
So my question is would you let another person know if their diaper/protective undergarment was showing and they obviously did not know it? Having started wearing protection on air travel myself, I would like someone to notify me (albeit a private manner if possible) if I was exhibiting my upper waist band / part of my plastic underpants (specifically in the back above my belt) while in public.
When I was about age 6 I recall seeing a boy at school bend over to get something on the playground and his plastic underpants sliding up to where I could see them. My first thought was to point this out to everyone for a quick laugh but then recalling how I wet my sleeping bag several nights at a camp when I was age 5 and my parents put me back into plastic underpants (which turned out to be good thing), I let that bit of humility sink in and decided immediately that causing someone else embarrassment was not right.