Response to post #4. Dogs don't hate uniforms. Mostly they hate people who they don't trust or who are in fear of them.
We had a UPS driver who delivered in our neighborhod, the dogs would jump in his truck and ride withhim when he made his deliveries. When he left the neighbor hood he would give them a treat and tell them to go home. The dogs would jump out and go back to their yards.
His relief driver showed fear and agression to those same dogs. They responded in kind. He was removed from the route at the request of the residents and never allowed to return.
I was a high mileage (75 to 100 miles per week) runner, door to door salesman and LEO. I was never attacked or bitten while engaged in those activities.