This story was sad, but I don't get why someone would take the dog to the mall just to leave it in the car for hours.
I've had to break a window once (with mall police there) to get a dog out of the car. A lady left her black lab in her black car with black upholstery and no AC or water, on the hottest day of the year a few years back. I saw the dog when I went into the mall for a short errand and when I came back 5-10 minutes later the dog was still there. I let the mall security know and they tried to page the owner through a mall announcement. After 15 minutes of no reply the mall police had to call emergency services and they told them to break the window because they couldn't make it for another 45 minutes (I ended up having to break the window because the mall cops were all worried about being sued). I stuck around for as long as I could after the dog was out, but got the mall security phone number and called periodically throughout the day. Apparently 4 hours later the lady showed up at mall security to report that her car had been broken into and that her dog had been stolen. The mall cop that I spoke to, who was there at the time and is a HUGE dog lover, said that he told her she would be lucky if the dog were stolen because it could have been dead, then he handed her the number to the local police and animal control and told her that they had her dog. Apparently she was pissed because now she had to go down to animal control to get her dog back, I guess a dead dog would have been much more convenient for her.
On the same note, I have to agree that a lot of people that see a dog in a car go straight into "OMG there's a dog in a car, it's going to DIE! Get it out, get it out!" mode. There's a guy that works in the same building that I work in that used to leave his dog in his van so that no one would steal his tools. This dog had it's own fan, water, food and cooling pet bed. The guy would also check on the dog every 20 minutes to make sure it was ok and to let it our to stretch it's legs. I came out on break one day to find a group of 4 or 5 people huddled around his van contemplating on breaking the window because the dog was "in distress and could die at any minute" (the dog was just sitting in the front seat watching all of the people gathering around the car). I pointed out the clearly working fan and water which dispersed the crowd except one woman who was adamant that the dog was going to die. Then the owner came out and she gave him an earful about how he was trying to kill his dog, he shouldn't have a dog and blah, blah, blah. So he proceeded to let the dog out of the van but told her to stand near the door. The look on her face was priceless when the cool air from inside the van hit her and she walked off in a huff!