Not saying "thank you"

I dislike when people don't say "thank you." I encountered this multiple times today. I don't know if it's this weather that are putting people in a rude mood or what.

(Source.)

But I did hold the door open for this guy today and looked right at him and smiled as he walked in, and he didn't say single word. Hurrumph. See I hold the door for him again.

*Rainbow*