I would not put a muzzle on my dog unless he/she needed to wear it. I feel this is signing the dog death certificate , some crackpot may decide to take matters into their own hands and shot the dog. Some guy went to a park in my city with a gun and the guy decides he was going to shot any dog that run near him . He shot and killed someone dog that was a very friendly dog.
I used a gentle leader on my last dog and some people thought it was a muzzle and would they would pull their kids away from my dog. I did not like people spreading rumors that my hearing dog bite people.