UK: random conversation breaks out when there is an unusual delay or we get stuck at a signal set to danger. After an initial silence, someone will make a joke, and then it breaks out. Those are good delays.

I talk to the same people on the bus every day, it's been 4 months now and it's fabulous, I'm never bored!

That's a global trend, not a local one.

I've seen it, but usually they are some brand of crazy.