Many people become greed if they know how to make money, and many of them fall because of the simple trick, so they lose their money. They know how things work, but the greed tells them that they can make more bitcoin by joining in those programs, and they forget that it is only a scam without a new way or old way with some modification. We can hope that many people can learn from that, so they don't fall with that offer.
Well, true I guess if the same message would have come from some unofficial account then people would have paid more attention but seeing big accounts tweeting about giveaway made many people trust them and in the end, ended up losing money.