This is very thought provoking and you make valid points. It's odd because where I live, it's very hard to find adoptable animals, especially kittens. I worked at a pet store and every day people asked about where to find kittens. I got lucky with my shelter cat. His post was online for maybe two hours when I saw him, and I immediately called the shelter to make an appointment.
But back to your OP, I realize that my location is an exception, most people want the youngest kittens and puppies and rarely consider adopting from a shelter, and yes, like what others say it is so sad to want to bring in animals from war zones if we cannot take care of our own shelter animals.