Thought this was an interesting "refresh" for comparison: http://www.washingtonpost.com/blogs...-browns-new-logo-is-completely-underwhelming/ Here are the Browns' updated logos (via @Browns) pic.twitter.com/3ZV4D5F6w2— Sunday Night Football on NBC (@SNFonNBC) February 24, 2015
Football, as with most American sports, was always viewed as a way for people to unwind and relax from their day to day work, not create more for themselves. Thus why its expected of the club to do most of the heavy lifting on things.
In this case I think it's simply because no fan group ever bothered to trademark the name. The fans did do most of the heavy lifting to create the personality of the Dawg Pound, but they just never asserted any legal rights over what they'd done.
I also don't think there's any culture of distrust or need/desire to be independent in most American sports.