Well I think we all have experienced this during childhood days but when you do this on adulthood I think it was a bit odd or awkward. Sometimes we are trying something new experimenting on every bet we had on gambling and it is quiet fun but not in a way that we end up looking stupid in the eyes of other gamblers. Superstitious belief is quiet common in gambling than any other activites.
Come on, where is your inner child? 
Adults don't have to totally nuke the child they used to be in the early days. Actually, what keeps us jovial, hopeful and playful towards the events in life is inherently connected to our inner child who never disappeared or stopped existing completely, but is just numbed somewhere on the depths of our unconscious, untouched by many, because they think it would be strange or inappropriate to awake it.
There is no better excitement feeling than the ones we used to have as children, so it's natural even adults want to rescue those emotions by reproducing them on their gambling sessions, closing their eyes on decisive moments, crossing fingers, holding something on their hands to calm down... Of course these are all superstitions, but more than that, they are also mechanisms to make the gambling experience more immersive and emotionally rewarding.
, like some of the billions of different stories, we talk about luck as a probability with an extremely rare level, but in essence, it also requires a broader view of learning and perseverance to achieve good results. The issue here is not simply about gamblers, but more broadly, whether people are aware enough to understand that we are just playing on a stage set up by others, and those who post it later. It's telling the players that they are blindly searching for what they have to offer. I look at gambling like that, so usually I don't care much about material things in this field, rather I understand the mistakes behind sometimes even the excuses about finding fun, but happiness. That joy I see in gambling is only a small part of life, so sometimes people complicate matters with tactics I don't want to deny, but it seems to be very small. 
