Big Dog Owners

I don't know how many times I've heard this line: "People are often afraid when the ... dog runs up to them ..., but they soon realize she's friendly" I wish these people would realize that just because a dog has been friendly with its owner in the past does not mean it's going to be friendly with a stranger in the future. And unlike, say, an unfriendly parakeet, these guys have rows of teeth designed for tearing flesh.