Yes, there are overzealous people who will deem an animal in distress and use this (and other similar) law to rescue an animal that doesn't need rescuing.
However, I think there are several factors:
1. There is no distinction between the person leaves the dog in the car while they have a few beers in the bar and the person who leaves the dog in the car while they pick up a to-go order or milk & bread, etc. simply because it doesn't matter WHY you left the dog in the car, it only matters HOW LONG you left the dog in the car. If you can pop down 5 beers in 5 minutes, but it takes the other guy 15 minutes to get that to-go order, then which dog is at greater risk of injury?
2. Rather than declaring the law as too vague and a problem, I think we are better put to educating the public (and all those overzealous folks) about how to identify distress and when to take action.
First, if all windows are rolled down, then simply providing the dog(s) with fresh water and keeping them in a confined environment (the car) is safer than opening the door and letting them out. Calling the authorities while you sit outside the car and watch the dog(s) in the car after providing them water is safer than opening the door and letting them out.
Second, letting a dog out of a car, even if it appears too dehrydrated/thirsty/heat poisoned to do anything, is risky. That dog could very easily get scared by you, by the noises of the street, by passerby, by other cars, or simply by being loose. If scared, that dog can rush into traffic. Or the dog may have issues and become aggressive or fearful and bite you or someone else. If you open that car door, YOU take the responsibility of that animal into YOUR hands - be sure you have a well-thought out plan first. Don't save the dog from death in a car to death by a car or worse.
Third, have you tried to locate the owner? Have you called the authorities? Have you made any attempt to resolve the issue without putting the dog in danger? Have you made a thorough check of the vehicle to make sure the dog is potentially in danger (e.g., is the engine running, is the A/C running inside, is there water in the vehicle for the dog, are the windows rolled partially down, etc.)? Make sure your actions are truly for the benefit of the dog and not just a "good Samaritan feeling" for you (yes, animal rescuers, charity workers, social workers, etc., can and do mistake one for the other).
By understanding the true risks of "rescuing" the dog, THEN and ONLY THEN can you make the right decision and use this type of law to help the dog.
As an animal rescuer, I have had many many many people rush up to me and tell me that I MUST rescue that animal over there. Whether it's a loose dog, a dog in a car, a cat with kitten, etc. I have learned to educate those people about the responsibilities of rescuing - it's not enough to just "get that dog so it doesn't get hit by a car", you have to have a plan for AFTER THAT - where will the dog go? who will care for it? how will they pay for it? It's the same here - it's not enough to just "get the dog out of the car", you have to have a plan as to how to protect that dog once it is out of the car.
1975 American Clipper RV with Dodge 360 (photo in profile)
1998 American Clipper Fold n Roll Folding Trailer
Both born in Morgan Hill, CA to Irv Perch (Daddy of the Aristocrat trailers)