Hi, it is normal, you can have a precise idea of what is accurately modelled or not on the scenery gateway here :
You can also contribute to the whole community if you want to model accurately a particular airfield, thanks to World Editor (WED1.6b2). You just need to create an account for that. It's a long work, but very satisfying. It is all free and you can find a lot of tutorials on the X-plane developers page, or even on youtube.
PS : I am not part of Laminar Research team, which is rather small. I am just a normal user who decided to contribute this way.
Best regards and happy flyings,