Several decades ago I knew a woman whose greeting was (take deep breath & out with it ) 'hellohowareyouI'mfinethankyou', then she'd skitter off into the rest of her conversation.
The person greeted had no chance to say 'fine, thankyou' or 'Not well, I've just been to hospital' or ...

I also find the 'how are you' greeting to talkback hosts a pain. Poor bugger just says 'fine' or whatever to his/her 30th caller ...

I've also known some wonderful people who really wanted to know how the other person was.

And I won't get into the subject of junk-mail callers - as soon as a bright cheerful voice warbles 'hello, I'm whatsit from (company)' I just hang up. They interrupted me, & I won't waste time on them, same with brightly smiling (young) folks who stand at the station entrance or on street corners trying to get folks to sign up for their charity or product.

sandra