That is a possibility and probably there is some truth in that. If there is free money involved, you will always have people that want to cheat the system by making multiple accounts or doing something else. It is the same for all giveaways that casinos do and not easy to stop it or to detect everything.
While I don't know the full story, it is interesting story when you think about it. Like you said, when there is rewards involved, people will always find a way to game the system and get the most value out of it for themselves. The BcGame giveaway ran for a couple of weeks and that's an ample amount of time for people to create new accounts and get some posts in before going ahead to claim the giveaway rewards.
It's weekend guys, what are you guys getting into? I took on some sport bets and my last game (Real madrid) in my tiny acca just played out well..