There is still a week left for the Christmas itself, I understand that some places started their Christmas thing a bit early but that doesn't mean everywhere has to start that early as well. I feel like windice will probably have another competition, maybe a bit more expensive this time instead of just 0.3 bitcoins (like maybe 1 bitcoin) but that doesn't mean that they won't do a promotion.
Because the advertising effect is better when you as a casino are among the first who launch (or tease) an event. People recognize things that happen first better. Everyone remembers who stepped first at the moon, the name of the second guy is not known to many
Christmas related marketing is not always that easy for these companies. They trying to make you gamble, it is not easy to giveaway something and then try to take it back. Whats the purpose of a casino?
Make you gamble and lose if possible, I mean that is how they survive, if they don't support you gambling then they won't have a chance to make money, if they don't hope you lose they have no chance of making money, in the end whatever marketing they do it has to be focused on you gambling and losing money.
So, when they do "Christmas" related marketing which usually is regarded as giving gifts, it is very difficult for casinos. How could they give you a gift when they hope you to lose? That is why I seriously think that competition is the best way to go, at least they "might" make you lose and give you less rewards.