If you’re not being purposefully obtuse, then let me clarify: I said boxes “etc,” but the question is clearly about laws and regulation around knives vs. Guns, as indicated by the title, not about how to open boxes.
The idea that an easy-to-open knife is “specifically designed for stabbing” is idiotic, but I guess that type of ignorant reasoning unintentionally addresses the actual question about why these absurd knife laws exist.
Also, for future reference, you can usually spot the questions by the sentences that are followed by a question mark.