There was a friend of mine who let his dog run in the neighborhood. She was a smart and friendly English Setter who loved everybody and ran and played with all the kids.
It never occurred (for some reason this doesn't occur to many pet owners, they truely intend no malice) to my friend that his dog was ever a cause for irritation due to where she was leaving her piles.
When my friend (a reasonable guy) was told about this it was taken care of fast and never a problem again.
I only had to be told, I mean my friend only had to be told once.