Much as I like him, Bob is known to be a bit volatile sometimes. Perhaps his comments in the restaurant thread are over the line a little. On the other hand, I understand why he would be frustrated, what with all the folks who hijack threads to a different purpose. Let's also be honest... how many of us would bother to dump a post (someone else's) we didn't like on a thread that had gotten rather large and hard to review?
There is also THIS to consider. If Bob chooses to dump a post, it is better than dumping a user account. A more measured response, I would say. My thought is that if you don't want Bob or other moderators to whack your account, but you want to abuse Bob, as an issue of fairness you have to give him some sort of middle ground response. Dumping a post is a lesser response than dumping a user. We already know that in the past, Bob has dumped a user outright. Does the vBulletin s/w have a way for the thread creator to mark a box that says "The author of the thread expressly dislikes this answer" ? I've seen some noise about removing reputation flags. What else is left to do when you can't "do nothing" but have no responses other than dump the user or dump the post?