I severely doubt you've tried extending compassion to any nonhuman things on their own terms rather than on ours. We're smart enough versus a dog to play a kind of "coherent extrapolated volition" game. What ought I to want, if I were a dog, but given what I know as a human? "Intelligence. Urgently. Food can wait, I don't give a damn if I'm cold or have fleas, fix my brain. I'm a fucking cripple."

That is what the starting point of compassion for all life would look like. So, when you consider the puppy-rehomers, it's pretty obvious they are just letting their cuteness instincts hijack their higher minds, and they want to spread the contagion.