No YANBU, you are being completely reasonable. I Live in London and these are some of the things that happen on a DAILY basis:
The pavement is narrow, I see someone coming towards me with a buggy, walking in twos etc and I stand to the side to give them room to pass and they walk past without even looking in my direction, let alone saying Thank you.
Give up seat on bus = no acknowledgement or thanks
Weighed down with shopping and DC on bus = ignored.
First in line at the bus stop, but end up getting on last.
Ca't get off the bus because people getting on won't wait.
Say good morning to people and blanked in return.
Groups of kids force me to walk around them or in the road because they won't move out the way.
People play their ipods so loudly I hear their music.
People leave their car alarms blaring because they can't be bothered to turn them off.
Angry customers swear their heads off in the shop despite the presence of children in the shop too.
HATE IT when I go to visit friends and they spend most of their time on their mobiles/phones. When people come to mine and the phone rings I keep the conversation brief because I have visitors
Shop staff are having a good old chin-wag while i'm waiting to be served.
I try to teach the DC good maners but wonder if it means they will just be walked over and have doors reboundiig in their faces, when they open doors for people they often get no thank you either.
Thanks for the thread, feel much better after ranting.