I've had that a couple of times before, last time with an "I can get the door myself!" scolding. I just shrug it off and think what a sad individual they must be if they take offence at common courtesy. I mean, I'll hold a door for anyone rather than let it slam in their face. It's not special treatment.
As a female, I really don't understand why other people take offence over this. I hold the door for anyone, as you said, it is common courtesy and it would even be more rude, if I let the door slam in thier face. If someone, male or whoever held the door for me, I would thank them, as atleast I won't have door slammed to my face. It seems, in this society, being polite and having manners is now offensive.
I find this quite funny. A few months ago I was leaving a train going onto the platform of my local station, about to ascend the stairs to ticket hall level. I saw a woman in her mid 20s really struggling to get a heavy suitcase up the stairwell. I said politely, "can I help you with that?" to which she grunted, "no, I'm fine". I walked up the stairs and looked behind me to see she was having a very difficult time, I wouldn't have been surprised if she put her back out and injured herself.
Another example from uni a few years ago, not the same situation but it had a similar theme.
I was in the union shop looking at some different types of train pass holders and I decided not to purchase one. The girl behind the till spots my lack of uptake on the purchase.
- Ah, I know what you're thinking, too expensive, right?
- No, I didn't like the colour... I mean, £2 is expensive for a pass holder but reasonable for something like er... Tampax [I mention Tampax because they're the next item on the shelf - but I've unwittingly triggered something in her].
- NO £2 FOR TAMPAX IS TOO MUCH MONEY IT'S JUST THE GOVERNMENT'S TAX ON YOU FOR HAVING A VAGINA
- Well... I....
- THEY PUT A LUXURY TAX ON IT
- What's a luxury tax... I didn't know that that was a thing...
- YES IT IS GO AND READ UP ON IT
- Why would they do that?
- ONE WORD FOR WHY THEY DO IT - PATRIARCHY!!!!
At this point I took my green tea and left.