We had a woman mail carrier briefly that carried dog treats and made friends with a lot of dogs in the neighborhood.
The only thing people have to fear from our Beagle is being slobbered on. 
Yeah, I subbed on a route that was "mounted", I pulled up to this mailbox and a well behaved black lab came over and sat down next to the mailbox. I didn't think anything of it and went to the next box and the same dog came over and sat down again. He did this for about five boxes and crossed the street when I came up the other side and did the same.
When I got back and talked to the regular he said, "oh yeah, I keep dog biscuits under the seat".
