Being in Tokyo, you're more likely to encounter certain situations than you would in most smaller cities. This trait is shared by places like New York City and LA. Specifically I'm talking about location shoots for movies. I run into this occasionally because I ride my bike along the Tamagawa river, close by one of the commercial film schools near Noborito. So, there'll be students out practicing lighting, framing, acting and filming on the banks of the river. Sometimes, the shoot will be right on the bike trail and I'll have to make my way through the crowds as they're talking out the scene. I've never seen the results of these kinds of shots.
On the other hand, about once a month, a TV crew will descend on the office building I work in during the weekend. They'll shoot in the 4th floor lobby, and they'll block the one running elevator until the shot is done. Kind of runs the risk of my getting back to my desk late and starting my next online business lesson behind schedule (hasn't happened yet, though) because they won't let me upstairs right away. It looks like they're currently shooting for a new series. I was once told that the filming was for "Tokyo Tower". 2 weeks ago, it was for the legal drama "Magerarenai Onna". Here's the official page. I haven't been able to watch this show yet, but I kind of look forward to seeing the lobby show up on TV some time (there are a few episodes on youtube now).
I have no expectations of my ever getting a walk-on scene.