The one time i'd like to see people toe the line

One of the most common problems in team games is that each worthless idiot on your team always plays for his own score and not the team objectives. Most manifestations of that mindset can be explained. I am not currently talking about spawn camping or ninja-looting or kill-stealing or any of the other petty greedy fixations of the worthless imbeciles in online games, but about a behavior which cannot be explained by selfishness alone.

Say you're in a team PvP game, be it isometric RPG-style, FPS or AoS, or even a team RTS. The behavior pattern is the same. In the instant when two armies clash, that utterly crucial first impact, there's one common rule:
HOLD RANKS !

That is not what happens in online games. Players mill about indecisively for a while, then something happens, combat is initiated in some way and... inevitably more than half instantly panic and scatter. This is not a self-serving action. It leads to a loss regardless of whether it increases your personal lifespan by a few seconds. It doesn't matter whether one side is winning or losing. It is not a retreat. People simply panic in fear of dying - virtually. They run in random directions, not always away from the fight, without actually attempting to help a teammate or attack the enemy.

Intellectually, i can see the instinctive behavior patterns which give rise to virtual cowardice but it remains as alien a mindset to me as an earthworm's aimless wriggling on the sidewalk. I cannot fathom what can be going through the average idiot's brain when he wets himself and scampers in fear of dying in an online game. How do they rationalize it? Do they? These are the same cretins who use 'it's just a game' as a catchphrase to excuse any immoral behavior they so desperately adopt in order to make themselves feel big.
Want to steal loot? It's just a game, go ahead. Want to download a cheat? Lighten up, dood, it's just a game. Want to use only one weapon because it's currently overpowered, ignoring the rest of the game's options? It's just game, who cares. Want to sabotage your team, kill some allies? Come on man, it'll be funny and it's just a game anyway.
How is it not "just a game" when those same macho troglodytes have to hold the line against an enemy attack?