I see your point, but I don't believe we have the same definition of "information-free". Unless I'm mistaken, upvotes are anonymous. A comment of "thank you" or appreciation is essentially a publicly identifiable upvote. The information being conveyed is to the commenter and that information is the appreciation of the comment from an identifiable individual.<p>In just about every situation you could say that greetings, salutations, etc. convey no obvious information. But I'm not sure how far we'd get without them. I personally believe that things like this are what maintain and bond a community. But that is simply my opinion. I'd take a thoughtful comment reply, even if in disagreement, than an upvote any day.