I think it started as a gimmick (I think it was introduced before I joined SN) but the community liked it so much we need to think how to build on that

I also feel the cowboy hats are similar to "ranks" in old-school forums (like bitcointalk) where you can immediately see who is "trusted" and who is new.

However, the hats are more concise and hidden since a individual comment does not have as much screen real estate like on these forums. Also, you'll need to use SN for a while to "get them" (not only in the literal sense but to also understand what they are conveying) :)