...and No "Thank You", Either!

I'm told that I obsess about silly things that most people do not consider. for example, if a person who gets paid to speak (news anchor, weather person, etc.) says, "continue on," I feel that I am justified in snorting derisively, despite the fact that the person on television or radio cannot hear me. I have also had it "up to there" with folks who use the singular "they" (as in: "A person went to the store and they bought milk"). It's not as if I don't already grind my teeth at night...I should not be subjected to it during my waking hours. However, it is just possible I have a little OCD and cannot let such things slide. I'll try...but there is one thing that humans do that continually intrigues me.
I routinely hold the door open for people who are either coming or going through the same portal that I am or have. It's automatic; I don't think about it as a courtesy...it's just something I was taught to do and continue to do. Not a big deal.
However, I am totally amazed when EVERY time I hold the door, the person or persons passing through puts out an arm to hold the door open...just in case I happen to have a coronary and let go? Just in case it's just a prank, and I intend to slam the door shut as they enter? Just because I look like a criminal who is waiting to accost unwary shoppers? I have no idea.
But it irritates me when it happens.
Maybe next time, "Get your own damn door!"
But probably not...as long as the person doesn't "continue on."