What's with the new show and completely pointless final episodes?

I just finished The Vanishing and couldn't help but feel that the final episode and the twist at the end of the previous one was a bit pointless? Twice now this new series has had episodes tacked on that feel like complete padding, and not where anyone wanted to end things off. Not going to go into too much depth just in case someone accidentally clicks this and hasn't seen the new show yet. What are your thoughts?
EDIT: To clarify, I am NOT talking about the "twist" at the very end of the final episode. That is standard Goosebumps affair and not what I'm criticizing. I like that, it's fun. I'm talking about everything that came before.