I'm confused, you say most of the dogs were from puppy mills but don't understand how I would want to get rid of puppy mills? I don't know where you live but where I am (Colorado) we have little dog shops at every corner. You can call them "breeders" or whatever but they are just "puppy mills" with a fresh coat of paint. It's fucked up seeing hundreds of dogs for sale at outrageous prices and know that millions of dogs are put down on the daily. We are better than that shit.
Also, I "volunteered" for a county animal shelter for about 80 hours in my youth. Trust me, I know all too well what our reality is and "how bad it can get".
I'll never forget the day I realized my reddit app (Relay for Reddit) had a drawer that pulled out by just sliding your finger to the right from anywhere on the screen. As long as you didn't slide from the left edge, it pulled the drawer out. Why we don't make that the default is beyond me.