Many people just don't care about honoring the integrity of the game, if they can gain advantage in the meta game. Of course motivation for the game dissolves under such conditions.
Tying a tangible score number to 'vague social approval' hits very hard. There's a sense in which people care about that by default, but have to make themselves care about the inner game. But appearing to have integrity about the inner game is a good move in the meta game, so of course the default move of those who don't care about the game but want to appear to for the sake of the meta game is to put up a front: the trick is that it's not real. If playing the inner game faithfully, it becomes trivial to disassemble their (fronted) position. But it's not really a game, because they're not playing but pretending to play. You're costing them meta-score! How dare you!
Anyway, I digress. This dynamic falls out of the incentive structure of sites like HN/reddit/etc which embed discussion/argumentation into quasi-anonymous social-approval-point-ranked contexts. Moderation can temper the most egregiously obvious of such behavior, but only that.
A reasonable strategy if you're interested in actually playing the inner game is to carefully check if there's any meta game focused cheesing going on before bothering to enter against someone. Do they make mistakes in rule adherence due to inexperience, or do they make mistakes in rule adherence that conspicuously always puts them in a meta game advantage? Do they adhere to rules even when it's _disadvantageous_? That kind of thing.
To return to the chess analogy... Don't play with people who blatantly return their own downed pieces to the board (or similar hijinks). They're just there to look like they're the kind of person who wins at chess, not to play chess.