Agreed; that's why I set aside invisible tiles of all kinds (About 1 row of tileset) I won't use all of them and some will be spare. I also keep the sprite tiles free until then when I can dump eye candy into them. Since TOM makes this difficult I am testing a different level editor which may have a better feature fr this.
Spambots designed for phpBB3 often make their first posts Markov text to try to appear human (to get past the "newly registered user" status), then they start posting their links everywhere. That same user tried to post something even more nonsensical elsewhere and has been nuked.