"To every thing there is a season." To "witness" to people in a closed, confined environment is the height of rudeness.
I didn't read where he said for someone to stand up and start preaching. I also didn't read where he told anybody they had to do anything. If someone approaches you and wants to engage you in a conversation and you don't want to talk about it; dont! That doesn't just apply to religion you know, it could be anything.
And, as we know from St. Paul, love is kind, not rude.
As I previously stated that no reply to the post was necessary as I would not expect nonchristians to understand. Since you reference Paul though, you may want to check out his methods of witnessing; uh... along with many other christians over the centuries. There's nothing unkind about sharing the Gospel of Jesus Christ. No one said anyone had to listen or even engauge in a conversation.
There were no 767s in St. Paul's day.