There are several ways to hack. For every one way game developers find to prevent hacking, hackers find at least a dozen ways to hack around it. That's the nature of gaming.
However, attempting to do so is a quick way to find your account (in game) banned and/or deleted/reset.
Though, it's your account, do what you want. Just don't come crying to us when you lose everything you worked for.
Though, to answer the general question of the thread, yes. It's hacking. Don't pay it much mind. GREE has been letting them sit there until just before the event(s) end, and then deleting there accounts. Lets them feel all special, and then when they go to collect, the find there account...mysteriously vanished. Bet you they don't submit a ticket asking why there account is gone. What do you think?