Greedy or Opportunistic?

Sometime back I decided that greed takes many forms and one of them is whenever someone passes you up with excessive speed or reckless driving. Then a few days ago a woman in a vehicle in front of me when around a slower moving vehicle that had cut her off (an elderly man was driving) and it made me think deeper on this subject. Was she being greedy by going around this vehicle in an effort to get somewhere faster? I decided no, she was not. I have come to the conclusion that in these scenario's the fine line between greed and opportunity is this: If by passing someone you cause harm or possible harm you are being greedy, whereas if you pass them with no ill consequences to them or anyone else you are being opportunistic. I know that this may sound trivial but it truly is not. I have a deep belief in God and I am trying to do the right things in life. I was driving along the other day when this vehicle was in such a big hurry on the freeway that because the lane he continued to drive in was ending he caused a lot of problems when he finally moved into the lane that continued on. I decided he was being greedy. Then, when the woman I spoke of earlier made her pass I said she too was greedy but thought more on it. I decided that I too would have done the same as her had I been in that situation and therefore that would have made me greedy. I am sure this makes it seem like I am trying to get out of being hypocritical and that is true but in a the right way. I wanted to get to the bottom as to what constituted greed vs opportunity in this and I feel I did that. I hope to only pass when opportunity presents itself and not endanger others by being greedy. This is not only for driving but presents as a metaphor for many other things in life.