Bored strangers is the embryonic stage of many, if not most friendships. The more exposure we have to bored strangers, the more opportunities we have for establishing friendships.
I've only had two of those, bur if there was ever such a stage with them, it was exceedingly short... maybe the first few minutes. Come to think, it's the same with friendships. My friendships basically formed with people who were going to be there for longer than I asked for anyway.
YMMV, but the only time I connect with a bored stranger is inside of a video game.
And romantic relationships.