I think @gandalf_der_12te@discuss.tchncs.de has it a bit off, because he sees the individuals as positive or negative agents. I'd say it's positive or negative social situations.

If you're playing dodgeball, the point of the game is to hit other people with a ball. That's the situation you're in and your social reward is in playing the game.

By contrast, if you start flinging food at a wedding, you do not get the same social rewards. The point of a wedding is not to physically dominate your peers.

In OP's Greentext, you've got a kid who is in aggressive, jockular friend circles where verbal sparing is expected and rewarded. Greentext would not be rewarded if he behaved the same way with his mom.

But it's certainly possible that if the mom was younger and in a social circle with more jockular members, or she was sparing with other old biddies on Facebook, that she'd drop the nice demeanor and come out swinging.