Kicking foam would be destructive and i could see it annoying more people than not, especially if you damaged their gear in the process.
Do you also oppose shield kicking? Cause it's the same thing. You are kicking foam. The shield might be more durable, but a kick will undoubtedly do more harm to the shield than a regular weapon strike.
Seeing as their is more foam to a shield, and that you usually kick the bottom part and hit with the top part, im not worried about it. Kicking the courtesy padding on a red thou, where there is less padding, less surface area to distributed it, and that courtesy is there to protect against accidental hitting, i could see more of a need to worry about it.
What about stepping on the haft of a spear thats been thrust through your lines to prevent the owner from pulling it back?
I second this question. Having read up on group tactics, I would really like to use this, hehehe.
Well, while i have done that and probably would do it again in the moment on accident, I'd like to think it more of a dick maneuver and that I would try to avoid it, just like i avoid stepping on arrows, swords, and shields.
Legally, it is not addressed
For safety, i could see it being bad for the weapon, and thus could cause it to "fail" in mid fight, and no one wants squished padding slapping them or a spear head falling off. Playability and realism it's perfectly fine, but it won't win you any friends.