You okay? Normally you make a lot more sense than this...
My approach: Since Gree knew about this error shortly after it was released, they should have taken the game down for maintenance, fixed the error and pulled back all the items from the package in question and refunded the player's money (or at least instruct customer service to take this approach for anyone who asked).
Your approach: you agree with the way Gree handled this, which was to ban some players right away, which then put their syndicates in a disadvantage during battles. Other players that bought the package in question were not banned until hours later and were allowed to keep their stat gains and the items they gained for their syndicates, which allowed them to buy more bonuses. In addition, Gree pulled back the gold in question (as well as all the cash in their banks and the current LTB's in some cases for whatever reason), and replace it with a quantity of gold they felt was fair without giving the players any option for a refund.
Since I didn't buy the gold and I'm not in a top syndicate (only a couple players in our syn bought this package as the rest of us play gold free) the impact on my game was minimal. However, I think it's crazy how Some people are trying to call these players cheaters when all they did was push the 'buy' button. Since you're okay with Gree's approach I guess you benefitted from this error either by buying the gold yourself or being in a syndicate that benefitted from these purchases. It's okay if you feel entitled to keep these items. It doesn't make you a bad person.