'Cause you aren't getting from one place to another as quickly as possible. You're just running laps. (at least in my opinion, feel free to let me know if I'm wrong.)
If you're just playing around a playground, doing whatever you can to get around, that's good practice for parkour, but it's not getting you anywhere, or away from anywhere, in a timely manner. It's just preparing you for when you do.
Now, "parkour tag" is parkour, as you are running away from someone, or chasing someone, using the environment to your advantage. However, if you're practicing running up a wall, it isn't parkour... unless you utilize the wall run to get someone in a timely manner.
Does that make sense? It's more of an opinion sort of thing, but that's the way I see it. If you're practicing Krav Maga, it isn't Krav Maga... unless you are actually defending yourself. The practice is just intended to prepare yourself for when you actually need to defend yourself.
