Today when hubby and I went to Target, we saw a little chihuahua left in the car. We watched it for about 8-10 minutes and when the owner didn't come back, I called the police. The owner arrived as I was giving the info to the police. I politely reminded her that it was illegal to leave her dog in the car. She yelled at her kid to get in the car and mumbled a few things then left. She was buying a vacuum and didn't think she would be in the store that long.
Nonetheless, the police took her info and will probably contact her to remind her that she needs the leave the dog at home next time. If they had arrived, they would have cited her for negligence or animal cruelty.
If no one is going to stay in the car with your pet, please just leave them at home.