I want to buy Supernatural strictly to get more content, and check out Moonlight Falls. I do not want ANY supernatural species. I see in my current edit panel the ability to turn off species. If I don’t have Supernatural installed, it is greyed out and says something like “you don’t have this EP installed.” Except for zombies - that’s not listed. Since all the other species that come with Supernatural are listed but that one, can I assume you can’t shut off zombies? If I can’t shut them off, I don’t want to buy the EP. I do have NRAAS installed, but not retuner. TIA!

Zombies happen at full moon. You can change lunar cycle so this never occurs. Some people have also made mods to have no zombies I believe but do not remember all of them.

you can disable generation of most of them in the settings. Though you need to exterminate existing ones (in the world installed with the expansion) manually.
For the zombies you have: http://modthesims.info/d/486695/no-...-2-flavors.html for example.

NRAAS allows to finetuning the matter, and also easy way to get rid of the species.

If you have Nraas MC installed: Click on an existing supernatural Sim, go into the Nraas MC option then intermediate there is a remove occult option. There is also an add occult option for it you want to try and play with supernatural Sims on a smaller scale.

Supernatural is a surprising favorite of mine as I do prefer more "realistic" type of gameplay. I love the clothing and furniture that came with it. And tho I don't always want the these supernaturals in my saves they can make a nice fun change to a more realistic play. I do suggest trying the Supernaturals there is quite a bit of game play to them and it is nice to try and experience something new and different from time to time. Moonlight Falls is a lovely town and EA really made an effort with the different Sims they created for it.