Much of it is just about popularity. So many people know wikipedia exists, so you get a certain number of morons who love adding random nonsense (I revert 10 to 20 vandalisms on the Transformers pages daily). Most people who are on the internet to add profanity or comments about the prowess of Chuck Norris to Wikipedia never even heard of the TFwiki. Just today I had to revert info on Wikipedia saying Mega Fox got her part in Transformers by showing up at Michael Bay's home in a bikini. This was unsourced, and sounded more like gossip than fact, so I reverted it -THREE TIMES. One anonymous user kept putting it back in. Yesterday I had a guy who kept atting random categories to Transformers articles - like adding "Category: Fictional tanks" Rodimus Prime's page. I had to revert many pages from him. Couple of days before that a guy redid some Constructicon's sections so they were intirely in lower case without any periods. They just make up randomness hoping some new fix-bot on Wikipedia won't spot it.