It's another hot day in fabulous Fenton. The perfect day to LEAVE your dog home in the air conditioning. Where in the good dog owner handbook does it say to leave your dog unattended in a car in this heat? If you are hot, the dog is hot.
A dog cools itself by panting. Cars heat up very quickly even in the shade. Try sitting in a winter coat in the parking lot, on a hot day. Now roll up the windows
It is wonderful to socialize your dog and take it places. Running errands with you on a hot day while you go in and out of stores is not the time to do it. This is a form of animal abuse. Many times over the years, I have gone into a store and had a store employee page a car owner by the description of the vehicle and the license plate number. I have also left the AKC handout regarding summer care and dogs, and yes, I'll admit it, nasty-grams on the car.
A dog in distress because it's owner only "went in for a few things", is a situation easily avoidable. Use common sense, leave your dog at home OR get grilled by the good Samaritan who just happened to notice your dog in distress.