I don't believe for a second that this isn't being done, at least in some capacity, for attention, otherwise they wouldn't post at all. People are still going to buy it and there would be no need to post things like "Aqua!!!!!". If you're going to do that, don't tell people not to ask for spoilers; they're just enticing people even more. I think they are having some fun in how much attention they have right now (their subscribers keep growing and growing). They seem to be pretty die hard fans, so they should know more than most how many questions about the story they are going to get.
I don't much care myself at this point since we are so close (Japan will have it in less than four weeks), but it certainly can drive one crazy listening to all these people who have the game or even claim to have it. On twitter, people claiming that they have the game are arguing with each other over the validity of their leaks, without posting any proof that they actually have the game. It's like watching two morons arguing over the punchline of a joke that didn't make sense to begin with.
I'm locked in for getting the game and I'm so used to spoiling myself in the past with watching the Japanese version when it came out months before my area, that I really enjoy spoilers. Perhaps these guys are doing it do to be respectful of people, but I really doubt it. I just think they enjoy having the power to confirm or deny what fans have been waiting on for so long. They're not bad people in my opinion (at least not on this basis alone), but I don't think they are doing this solely because they feel they can help the KH community.
It is a shame though that SE was so close to releasing the game in a spoiler free environment; the game went gold and nearly good to go.