Lunatics vs My Service Dog

Ok full disclosure, I have a small service dog. I chose a small breed because I travel nationally for work, but the generally public cannot f**king handle it and I don't get it. We dissect grown humans psyche when seeing a dog and the unhealthy ways they approach it as I also navigate healthy ways to deal with it. Our weekly gas station snack trip had us walking out of the gas station like "this is an episode" since a grown ass woman came at me like a fast zombie; not a slow zombie. This happens to me more than I'd like and I wanna know why. Why cant folks mind their business, and why does having a service dog make my life easier and also so much harder.