Should I or Shouldn't I

Everyday and everywhere, during the normal daily activities, I always encountered some circumstances that creates war inside my brain, "Should I or Shouldn't I?"

For eg. during my bus ride to office, a lady listened to their MP3 with volume set to very loud. Should I ask her to lower down the volume?
Well.. it's very interesting to see how other people react to this. Some people will start to stare at
her with 'that kind of look'. But nobody really dare to say it loudly in front of her to reduce the volume level of the music.

After this incident, I noticed that more and more people are actually having this habit. Some of them even listen to the music without using earphones.

Is it Asian norm to just keep quite to avoid any conflict? I believe that if it happens in other places, eg US, some people will just complain directly without any hesitance.
I wish I have a little bit of their thick face attitude in me sometimes.
So that I will have less 'Should I or shouldn't I' war inside my brain.

Happy working all..