In the beginning of our creation we believed the world was flat. Which gave us only flat beliefs and dreams. After the first murder our lives rounded out. With those darker thoughts came darker beings. Gotham is a city in the world which has an unrequited amount of darker beings. Dick Grayson chose to live their specifically because of that. So when he finds a vampire at a street corner he's not surprised. The following events after the meeting did, though. (Vamp!Jay, Young!Jay, Young!Dick)