I thought abou this, because at first they seemed silly to me, but as I see it, it's kind of like in the mtb world, where we have a range of xc hardtail, trail, enduro and downhill types. Each type is perfect for its own type of terrain, but there's overlap between them.
So you need 4 bikes for a ride around Epping?
Hide them in the bushes and swap them based on terrain!