As a few posters have said, it's funny how it's only ever WOMEN who are targeted, and never men. Other women have a go at them, and MEN have a go at them, but no-one seems to have a go at a man.
Probably because they know a man is more likely to say 'fuck off you nosey cow.' Then again, as this thread illustrates, some women will say that too. I would, in situations like this, and I have done. I have a couple of friends who are the same as me too.
My one friend (I'll call her Lisa,) is disabled and has a blue badge, and she is 45, but looks more like late 30s. She has had nosey people (usually women,) scowling at her, because as she looks young-ish, and isn't in a wheelchair, she obviously isn't actually genuinely disabled. 
One nosey woman glared at her one time (2 years ago,) and Lisa said 'what are you giving me evil looks for?' The woman said 'you are in a blue badge zone, with no blue badge, and are clearly not disabled anyway.' The badge WAS in the window, the stupid woman just didn't see it.'
Lisa lifted it up and waved it in her face. 'There you are, my blue badge in all its glory, with my face on it LOOK! Do you want to see my letter of entitlement to DLA and ESA too, and a doctors note confirming my disability, you fucking nosey cow!' 
The woman went flame red, and skulked off like a scolded chicken, but fuck me it was a priceless moment. 
Hopefully the woman will think twice before sticking her nosey beak in where it isn't wanted again!
And no, it doesn't follow that someone is 'not in a normal state of mind' if they confront people like this. As @XenoBitch said, some people are just opinionated arseholes, who think they have the right to police other people. People need to stop making excuses for people, when the only thing wrong with them, is that they are bloody rude, obnoxious, entitled, and opinionated!