Foxtrot Fallout
That's the chance you take with these things. It's like those Gold Gens for Gold they sell sometimes in Mecha Neko. Sure you buy a pack that opens 100 at a time for 1.5 Billion to get a chance to win 1 Trillion, but you also might only get 300 Million.
It's common but it's how it is.
Since I don't buy gold gens, I cannot rely on that analogy. However, since I am familiar with RIGs, it would be the same as saying that there is something wrong with the coding if a person bought 4 RIGs and everytime they were granted the same colored item everytime.
Since we know that there are way more than 1 common item (and in multiple colors) in the RIGs, it would be safe to say that something is wrong with the coding if a person was granted something like that over and over after opening 4 RIGs consecutively.
Thing is, this isn't just some RIG that leaves within a week or two, it's charm generator in a gold shop. And it looks permanent.
If it's going to stay in there, then something needs to change about how it grants when people open one right after the other.