Glad my name is not up there
There are a number of other people who do similar stuff (quit etc...), but since they have many less games, it is not held against them as much. Experienced players are expected to understand somethign of the etiquette and expectations of the other players in a skilled game.
An example of something a less experienced player then those above did to me recently is that they went AFK for a bit, come back and found they have lost a lot of their fleet and quit (they left their fleet attacking an enemy world). They don't stop and go - wait - I have a lot of credits resouces to either rebuild my fleet or give resources etc... to me before they quit... They just left and opened a hole in the lines.
The main thing to remember here is that How is not having a go at new players not being able to stand up against veterens - that is expected and he knows they will get better from experience. He is complaining about people with a lot of game time that should know the game, game mechanics and a fair number of the players online upping and leaving, thereby unbalancing a game.
When playing a game with a large number of skilled players, losing one of them and getting an AI replacement is a BIG disadvantage (as opposed to a newb where the AI is often an improvement). Losing that ally on a flank (even if they are losing) when they are a reasonable player is a killer blow as it allows the other team to attack that flank. Quite often, the losing player just needs to hold long enough for support to arrive. However the following occurs if they quit:
1) The AIs won't co-operate as a human would and sacrafice their fleet to hold a flank while they are reinfocred. The AI pulls back, letting the opposition through the choke point.
2) The extra time a human would take delaying the opposition is often the difference between your team being able to respond and support you (even if you are down to your home world) vs steam rolling the AI and into their flanks... Even holding them for 5 minutes extra can be enough for an ally to kill another player and come support you, as opposed to them having to face the bigger threat, thereby letting the almost dead player back into the game.