User blog comment:Poseidon133/Why do some wikis have talk pages?/@comment-2.96.23.242-20150416112125

Another reason not to use message walls or article comments is that they are propietry. As far as I know, there is no way to transfer content created with these features to a new wiki.

If you ever want your wiki to leave wikia for a new host, you'll loose all your messages and comments.