I know what it does. But in relation to this: Allow more than 1 comment upvote in 5 seconds, the first answer seems to imply that he would prefer people not vote that much on comments, and too many votes on comments is a bad thing.
I know that on SO, I have >400 comments, and not a single one at +10. Only a few even make +4. I hardly ever see comments voted that high unless they are very old and on old popular questions.
It seems that really, the SO zeitgeist there (which is assisted by limiting commenting upvote rate) is in conflict with the badge.
Obviously, comments are really useful - they are the common way to ask for clarification on questions, for instance. That doesn't mean they have to rewarded specifically - once you have clarification, you can give a good answer (and get rep from upvotes).
Edits seem to be given more 'rep' here - literally and figuratively. New users can't add comments (to ask clarification), but they can suggest edits. True, there is a review process around edits to keep the junk out, so maybe that's why. Edits also provide rep up to 2k, while comments, even when you're allowed to post them, don't.
Just trying to get the general gist of things.