Why are so many Amnesia custom stories so similar?

[Hardarm]

And, after Sir Pewdie started playing Amnesia, many many people wanted to make him play their custom stories. So they tried to just do something, so you can say, "MY CS GOT PLAYED BY PEWDIE :33".
They didn't had the aim, to create something new... They followed the first tutorials they found, and the most famous tutorials simply start up like this. Of course, not only pewdie-fans did that, probably everyone got to those tutorials, when you start making mods.
Let's create a Startroom. Fine, now we'll do a hallway and yay, you got your very first map !
the tutorial-guys simply explain everything by the most famous/easy setups. That's a fine idea, because starting with new, and complicated things would be... not that awesome.
And those tutorial maps, often get posted on moddb. I mean, that's not bad, you can get feedback for your really first map, it's fine, and you obviously mainly got those maps.

Just view the best rated for example, and you'll get other ones, really good maps. Like White Night, La Caza, House of Creep. (trololo)

House of Creep? wut no. maybe the "(trololo)" could be marked as making the last thing sarcastic, but not sure everyone will understand lol