Why don't some people thank you when holding a door for them?

People don't say thanks? I've always got a thank you or thanks.

They're either preoccupied or Danish.

Everyone always in a rush London is the worst especially rush hour everyone's on there phones.

No all of them right?

i think they think they deserved it, so that's why they don't say thanks or an habit from them, who always visit a shop or restaurant or hotel which always have a worker opens the door for customer

I'm a Gentleman and I always hold the door for strangers and I never expect a "thank you" so it's not like I'm gonna throw a fuss over it.

or french (or more specifically parisian). those mavericks do not subscribe to social etiquette. i like their style

Hold the door, but block their path. Don't move until they look you in the eye and show some respect.

Same

Don't think anyone has ever not said thanks to me. May not be thanks all the time, but it's around those lines.

Some people don't like being beholden to people.

When you hold the door open for people, you're essentially demanding they say "thank you", and by doing that it creates resentment.

It's dumb and petty, but there it is.

Try not to let it bug you, it's just human nature, they probably do it instinctively for the most part.

Great point, and very valid.

Also, you never know what some people are going through -- sometimes they're just too pre-occupied mentally to notice or respond.

exactly. My general rule is give people the benefit of the doubt. For their sake, yes, but mostly for your own.