The double chip thing might not be as profound as the other examples, but at least you won't have to wait until practically the end of your life to enjoy the moment. And yet, the double chip drop has a lot to say about the nature of such things. Observe:
1) Unintentional by Design
The vending machine is designed specifically so that only one bag of chips will drop at dispensation.
2) Undesired by Others
The operator of the vending machine likely takes a loss when dropping extra product at dispensation. They likely put a lot of effort in preventing the machine from dropping more than one bag of chips, loading the machine properly, maintaining equipment, etc.
3) Uncommon, Really
Really, think about every time a vending machine has worked either normally or against you.
4) Uncertain Results
Even when it does happen, chances are you didn't even realize that it was a noteworthy possibility. Even if you did, there is a significant risk of the product bunching up and becoming double-stuck, pinned on the walls or glass, hopelessly jammed.
My point is that these things that make life feel worthwhile for even just a moment have everything arrayed against them. In a land of predators, the worthiness of our lives are always up against dinosaurs.