For what it's worth, this post was the initial complaint, and implied that people boasting about their good luck (drawing rare character frags multiple times) would lead to a lowering of the % rate of boxes.

I'm pretty sure they don't lower the rate of the boxes (at all, not just due to too many people getting stuff), but I obviously have no way to prove that. It's fine if you want to be skeptical and su*ious of them, although I don't really see what that accomplishes.