We all know gambling is random. We like to call it as "luck" as it sounds cute but it's like "choice of odds" in mathematics.
I'm an atheist and when I started to play, I had a fun experience despite of what I won or lose because I bet small amounts. Then I got addicted because of some big wins so I started to gamble much.
Even if I wanted to think that maybe my winning and losing isn't getting impacted by anything external, I believed otherwise. I believed my winning is the result of the color of the shirt and wearing, music I'm listening to, time of the day etc. Then when I lost big, I prayed to God to help me win/recover. I saw gambling as life and winning is heaven and losing is punishment from God.
Then slowly I stopped and the addiction got away a bit.
What's your opinion, do you believe in God/power that you think may help you win? I think gambling has the potential to turn an atheist into theist because of fear/risk it has.
If you relate gambling with religious point of view, then you know atheist has no religion and he don't pray to God, and about superstitious, it is just like judgement, you can called we judge and guess which bet will win.
Actually you asked a deeply question, but as long as i think, gambling is a game, if you compare gambling with other games then you will never ask it.