It makes sense to me when a rescue will purchase a pregnant female to get the puppy making machine from the rescue. But what bothers me is when you see just puppies at some rescues and no a regular basis. To me there are HUGE RED FLAGS all over that picture! Most likely this is a mill looking to make money while posing as a rescue.
The puppies had to have come from somewhere and the mom is who needs to be out of that horrible place.
If a rescue has an occasional litter of puppies that is totally different than puppies only. Another thing to be aware of is that the rescue has a 501c not for profit registration. A good rescue will spay/neuter, fit the dog to the home and take in dogs with all types of needs.