I realize that not everyone is a dog owner, but I don't really see this as a "dog issue". I think it is an issue of what many of us have devolved into as a society. As a child, I was raised that I had no right to encroach upon someone else's "space" without at least asking permission or engaging the owner before entering their space. I didn't go up and sit on a stranger's porch or start playing with the neighbor's children's toys in the yard, without gaining permission. Those type of civil niceties are going by the wayside. I don't doubt people are "just trying to be friendly" (in some cases), but "being friendly" shouldn't signal a dismissal of common sense rules. One can be just as friendly (and perhaps much safer) after asking if it is OK if I pet your dog.
I agree with all of that, but that really doesn't address my point. The reason I see these as separate issues is in a friendly or unfriendly neighborhood, if people employ the simple common sense tactic of asking before reaching for my dog (and risking a potentially nasty outcome), a possible unpleasant outcome can be avoided. PLUS, there is a greater likelihood that a negative response from me would be avoided. This remains the same whether the neighborhood is animal friendly or animal unfriendly (but I do agree, I much prefer a animal friendly neighborhood).
I don't see any of this as a major concern, only that I think that there are reasons for why people feel entitled to approach someone else's space. I do not necessarily ascribe negative or nefarious intent to their actions, just that there are reasons for them.
I don't think this is common sense issue. For it to be common sense, it has to be common knowledge. Trespassing and stealing people's toys are common knowledge as bad manners, petting the little dog isn't... I don't know if you were raised with dogs, but I was and I know I am biased for it. My wife wasn't raised with dogs or any pets at all and having watched her learn while training Beignet has been an eye opener.
A lot of times, people just don't see it as encroaching on someone's space, they view the same as a friendly greeting like shaking someone's hand. Some people are also just naturally friendlier than some people. Everyone knows that way too friendly person that gives hugs to everyone.

Not playing with a cute little puppy dog isn't something we have ingrained in our society to make it a common sense thing. It's the exact opposite, he/she is our best friend and some are treated as well or better than our fellow humans. If we want it to be common sense, it's up to knowledgable dog owners to continually educate people to make it common knowledge and part of people's common sense toolbox. Think about how people do it in the Movies and on TV... I know it's well trained animals that have had prior experiences with the actors, but not everyone does and that's a lot of people's only lessons with dealing with pets.
I am all for giving animal lovers a little lee way and maybe some education to help them next time for the next cute little doggy they meet...
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