The practice and the believe of voodoo to work or make ones to win in gambling is just an act of lazy gamblers which believe gambling is a quick to rich scheme where in the end gamblers winning level are determine by strategy and luck.
Perhaps, that person is very desperate on how to win in gambling games. They tried to believe in voodoo and try to use that "magic" to help them to win. But we don't think that they will win the game as in gambling, that thing will not help us, but we need the luck to get the win. If they play a game like a poker or sports betting, they need to have a strategy, information, and luck. So perhaps, voodoo is still used by some people who really believe in that thing.