Do you need a bunker to buy an MOC?

Excuse me, could you elaborate on the necessity of owning a bunker in order to purchase an MOC? Is there some sort of security or storage requirement that I'm unaware of? I'm genuinely curious as to why you would mention a bunker in the context of acquiring an MOC. Could you please clarify the connection and what role a bunker might play in the process? Thank you for your time and consideration.