good manners and intentional dumbing down

Two things to mention today, please bare with me, you may consider this a rant...

On Wednesday I went to a charity shop.  It was a charity shop I have never been to before in a not particularly nice part of town, it smelled bad and the people in there were weird but I did find a useful vase and a tea cup that I am going to decorate, anyway, as I was leaving, two men were approaching the door from the outside as I was approaching the door from the inside.  I opened the door and I suppose I expected the men to let me go out first before they came in (as in the style of people leaving the tube), but instead they came straight in which I held the door for them with not so much as a second glance from them let alone a thank you, I was most irked and felt like saying "no really, you go first" in a sarcastic tone (I refrained due to the aforementioned non-niceness of that part of town).  What has the world come to? I firmly believe that good manners are a sign of civilisation so I can only deduce from my distressing Wednesday experience that we are becoming less civilised.

And another thing.  Why is it that in a class of 30, children choose to reduce their intelligence level to that of the lowest common denominator?  In my world it make sense to look up to the intelligent kids and to wish you were like them, to envy them, but in the real world all the children in the class dumb themselves down to the level of the one or two idiots in the class.  Really, I ask you, what is the world coming to?