Because I just noticed it. Look at this Wikia's activity, and see the energy drink pages and "Bathrooms" page(s).
It's an unknown contributor doing this. You can see his/her IP from his/her userpage.
Thank you for your help cleaning up. I haven't been too active as of late. I'll try to be more on top of this but please let me know if I miss anything!
To All Users Noticing Vandalism: Please report any vandalism here and I will take care of it ASAP!
What do you think?