I try not to lock threads too often, out of 700+ threads there's just a handful that has been locked. It's only when they get way off topic (And yes a thread can get off topic even if it's located in the “off topic” section 😉 ) or contain posts people might find insulting.
At the moment “one word games” and similar threads are treated as “post boosting” threads. Even if that wasn't the intention of the creator of the thread.
I'll look into adding a forum (or some kind of chat) just for word games and extremely off topic chatting where posts aren't counted. There you can go bananas if you wish 🙂