All thanks for the replies. Makes more sense, but I would have put it in as "this defense system needs X amounts of this rare fuel Y each Z" (or, maybe, bring a statistical aspect into it: "the Foo in your bar are wearing out faster than usual. Please make sure you have spare parts"), not as "yes, you have a zillion extremely powerful guns, but if you don't pay rent in time, we, will take your guns away from you.". This, to me, makes this universe feel like some toy system with some all-powerful entity who really is in control (a bit like Q, but less disinterested).
Also, what would an all-powerful entity need that money for? It would have to be some accountant-deity to enjoy such regular payments. Or was that apparent glitch that showed the bill as paid to some part of the fun?
Also, what would an all-powerful entity need that money for? It would have to be some accountant-deity to enjoy such regular payments. Or was that apparent glitch that showed the bill as paid to some part of the fun?