I think you meant to say that people are so absorbed that they never bother to take notice of the little things. Your story certainly rings true for anyone who has “blended in” to the situation. Nice story. Might want to double check your punctuation.
This is a great scene. You’ve managed to develop John very well through subtle action instead of just outright stating his characteristics. He’s just your typical egotistical, self-centered tool. Hopefully he gets punched in the face!
Like stargazer1960 said, you need to check your punctuation, mostly where commas are concerned, but otherwise this is a nice little story.