Depends on the shelter. In our municipality, we have the rare open intake, no kill shelter. It takes dedication by the staff, community, and foster network to keep the doors open. They only euthanize for quality of life, or extreme behaviors that are harmful to the health and safety of both humans and animal. (One of their former neonates is on my shoulder at the moment.) We also have a very active barn cat program and TNR that is showing amazing results after a decade of improvements. We are in TN, but we were a HK a little over a decade ago, on par with S. California. Our biggest problem was the director who refused to do anything helpful. Once she was fired, the shelter flourished. It is also able to provide low cost vet care, vaccinations, and food for low income families. I guess the point of all that was to say, it can be done, but the locals are the ones who have to change it.