I haven't volunteered with rescue since I brought Norris home two years ago, because I haven't really had much time. But when I was there I discovered that a lot of my thoughts are controversial among the rescue crowd.
For example, I think everyone who applies for a dog should be evaluated on a case by case basis and not immediately told "no" because they don't do everything the same way you do. I believe in having an open discussion about these things. I think with an open exchange of ideas and information, many more people would walk away educated about the care of dogs. However, a lot of people would rather just reject people and send them away.
I think shock collars (stim collars, whatever you call them) shouldn't really be used. I have seen way more issues with dogs trained using shock collars who were neurotic wrecks, than with any other tool. Even most dogs on prong collars seem pretty normal. Dogs on shock collars are on edge all the time because they never know when a shock is coming, because people suck at timing, and also telling your dog to "come" and then shocking the crap out of them when they ignore you is a terrible way to train a recall. We have had dogs come through rescue with burns on their neck from misuse of shock collars. Dogs have the mental capacity of a four-year old child. But we would never shock four year olds.
I have no issue with people keeping their dogs intact. I have no issue with cropping/docking as long as it is done humanely.
I seriously judge people who keep their dogs TOO FAT. You are CRUEL if you don't care that your dog has trouble walking, has trouble breathing, could get diabetes, orthopedic issues, etc etc. Your dog SHOULD NOT look like a walking sausage! A little chubby but can still be a dog, yeah you get a pass. But when I see dogs that look like end tables, I just want to rip their owners a new one.
And the BIG controversial opinion, that I cannot mention in rescue circles unless I want to be almost literally tarred and feathered, is that I don't think it's wrong to euthanize a dog for aggression. Seriously, if the dog is dangerous, and efforts to train have failed, I will not fault you for choosing euthanasia. Owning a dog is supposed to be FUN. It's not fun when you have to worry about your dog hurting you or other people. It's not fun for you, and it's not fun for the dog who's living his life so completely stressed all the time that he feels the need to bite people.