I don't think anyone at WHBQ-FM knows the meaning of the word "tread", unless it reffered to the condition of the Q-Bug's tires. ;D
Seriously, I don't think they would have a problem with this. Otherwise, Burns could sue every traffic reporter in America who said something like: "Traffic is movin' along on I-55", etc. The way they'd get busted, IMHO, is if they appropriated the phrase as part of their station name, and used the "Movin'" logo. If anything, Burns folks were probably watching to see what was going on, and chimed in by saying this is not one of their launches, just in case. If they really wanted to do the format at WHBQ (which I doubt), they could...just change the name to something like "Rhythm 107.5", or "107.5 The Party".