While I won't condemn you for doing what you want I will agree 100% with this. I've had some of the best dogs money could buy through the years and the mutt I have now is the best dog I have ever had. Better than the two pure bred labs I've had. She's part lab, part bassett, and you couldn't ask for a better family pet. It isn't even possible. Picked her up at the pet shelter for $50 several years ago.
We also recently rescued another Dachshund. We have one that we paid $400 for 14+ years ago and decided to get another to help the kids through her end of life when it comes. The new one cost us $100 and is just as pure as the other.
I'm not saying that rescuing a shelter dog is for everyone but there are a lot of good animals out there that need a home and another chance at life.