The OP's reference to "pets" is confusing. Most people who have chickens as pets are nearly devastated by a predator loss. Personally, I keep a flock, with the idea that birds come into and out of a flock, but it still does upset me when I find a bird torn apart.
If I read the post correctly, you want the birds to stay out of the garden, and live off the land in a natural non-restrictive setting. You only want rescue birds to have a quality of life.
I agree with your husband, this is a romantic view, not a realistic view. The person giving the birds away is solving his problem and responsibility. The birds are going to cause a lot of problems in your garden, and going to be eaten by predators. If you just want to feed the wildlife, that is your decision.
Mrs K