Where are the Manners??

Recently, I find that people are getting more and more rude.
Went Azzucar for SoS yesterday, We were there early and got ourselves a nice table. And the table beside us gotten more and more crowded as time goes by. I'm not sure why by the girls at that table likes to sit at the couch that is facing the dance floor. Its fine for sitting there, what is not fine is when they just sit down at our side of couch without asking if it is taken, and the most important thing is, Bear's bag and belongings are there. But they just sat down leaning onto her bags, where there are still chairs around. What is most ridiculous is when one of them 'accidentally' sat down on our table and spilled 3 of our only-drank-a -sip beer onto Bear, they did not even apologise let alone say compensation. How rude can a person be. What's worse is she gave a 'its not my fault by your fault for putting your beer on the table' look. When Fiona was putting the empty glass onto the table with a loud 'bang' and say that we have not even touched our drinks they turn and stare. It was until later, after demanding that they ordered our beer for us.
Though I am not really affected by the incident but I still find it maddening to see people being so ill-mannered, didn't even apologise for doing something wrong.