In the first episode of the show, there's this exchange:
Axe Cop: I just want to rent a dinosaur horn.
Dinosaur Horn Store Clerk: The only reason I'm recommending you buy it is to save you money.
Axe Cop: (Sigh) But it's cheaper to rent.
Dinosaur Horn Store Clerk: For most people, yes. But not when you keep returning them late. I mean, just do the math, alright?
Axe Cop: I always do the math and it's cheaper to rent!