Uh, why do people think that MC will be turning everyone into a vampire? He wants to turn OL into a vampire, period. The future encounters have nothing to do with this specific plot. Yes he might want to turn some of them, but then again he might not. These are different people we're talking about, each will have their own reasons to venture into the night.
All I've seen here is that the sleep shop will get more costumers and this plot will possibly the main point of the series from now on.