It's a good way to preemptively color the reader's perception of your comment. Makes you seem more reasonable and knowledgeable when you seemingly recognize the

It's a good way to preemptively color the reader's perception of your comment. Makes you seem more reasonable and knowledgeable when you seemingly recognize the controversial nature of what you're saying, even if it isn't actually that controversial at all. It's a commonly-seen tactic on reddit.