@Soy_Magnus @shortstories I might as well throw it all in this reply, but most of this is directly referring to OP.
>team sports involving balls lead to poor moral character
I disagree somewhat: I believe *watching* team sports (of basically any kind, including so-called "e-sports") leads to poor moral character.
This distinction will continue to be important.
>set up a us vs them mentality [...] on the basis of random assignment into teams
This is actually a good thing, given one condition: That that assignment doesn't last. With children the results are questionable because children are cliquey little shits, but around the latter end of puberty it becomes extremely effective to make today's enemy tomorrow's friend and vice versa: It teaches you to not hate trivial "enemies", to not take the game seriously; to focus more on the benefits of the training than on the score.
Again, watching sports rarely involves such rearrangement of the "fans", they entrench themselves and build grudges, leading to exactly that problem.
Bread and circuses are indeed effective against the audience.
Counter-point: Unorganised games with friends. Cricket makes a good example because it's reasonably easy to adapt to a teamless mode: Whoever gets the batter out becomes the new batter, bowler just rotates whenever. Nobody keeps score beyond "he did really well".
This still holds with, say, soccer, you can divide in half and go for it for an hour or so and then go back inside.