unacceptable social behaviours

Some of the most unacceptable social behaviours I cannot tolerate as a person are:

a. A person not saying "Thank you" after I asked him which floor he is going to. Do I look like a bloody lift operator from the 70s? I am polite enough to ask and help so I expected a very simple and free "Thank you".

b. Bumping into me without saying 'sorry'. I will say that to you even when you are the one who do that, simply because we are living in a very crowded island and I felt apologetic that I maybe obstructing you.

c. Talk loudly on the mobile phone on a bus. I cannot stand it when people talked at the top of their voices as if they are in their own living room. I am not interested in their gossips or their personal information, so spare me.

d. A person sitting back facing me when we are supposed to be sitting at the same table. Even if I dunno the person very well, sitting with your back facing me is plain rude and unforgiving from an adult. You can ignore me completely but showing me your back belittled me. The most intolerable thing will be when we actually know each other for years and the only time that person stop showing his back is when he is drinking or eating. Someone did that to me a few years back and I completely ignore that person till now (actually for other reasons). Someone did that to me last night and I am still thinking how to react in future. I had to down some alcohol last night so that I dun get frustrated.

I maybe very patient, kind and helpful to many people and co-head a charitable organisation, but I have my own boundaries and definitely not a 24hr walking charitable group.