I only have one snake myself and I breed my own rats. It's fun to me, except the one male I have can get stinky sometimes. As for breeding them for food/attachment, I'm only really attached to my first breeding pair, Wendi and Bluey, and maybe a few I know I'm holding back. When you have 8-10 babies being born, you can't be like 'oh he/she is soo cute I can't feed him'.
It's a great way to make a little side cash too. I don't have pet quality vs feeder quality, all of my rats are friendly and are suitable for pet homes. I sell my extra rats (I do only have just one snake) to pet owners and my small local pet shop will also buy the females.