Well that's a fun story and you sound completely level-headed, it does not seem like you have anger issues at all.

I dont especially feel bad for people who let their animals roam free when something happens to their pets. I feel bad for the animal, because their owners are too selfish to take some basic precautions to keep their pet safe. If your animal is outside and not contained in a fenced off area, it should be on a leash and under your control. Shit, the dog could have been run over by the driver as they pulled onto the property, if it's running around freely.

While I agree a driver shouldn't make a delivery if they don't feel safe, sometimes it may be too late for them to realize their is a loose animal before they are out of their vehicle. Id also bet 99% of the time, someone who is selfish/lazy enough to not contain their animals are the exact type of people who would call Amazon and demand that delivery driver be fired for refusing to make the delivery. "Where is my package? I dont care if the driver was scared. My dog is a sweetheart, he wouldn't hurt anybody. The driver should know that."