More than once I have heard "I bought that betta (a fish) because it was dying in that cup with only half inch of water". That is basically how stores display their betta fish. Of course, no fish can last long in such condition, but that is not the point here. The point of today is, quite a few people buy animals from pet stores just because they see the horrible conditions the animals are in. They decide that buying the animal would be saving their lives.
Sometimes the people who rescued these animals know exactly what they are doing, and they are totally capable and prepared to take care of the pets. For example when someone who already have a lot of fish tanks and fish at home with extra tanks to spare, he or she would have no problem taking care of one more fish. In that case, the animals being brought home from the pet stores are saved.
Equally as often, many people who have no idea what they are doing still bought the pets in an attempt to save them. Sometimes what I read is more like "I just saved a betta from the pet store, now what do I do?" it usually does not end well for the pets because their new owners lack of the capability and preparedness to take care of them correctly.
What I think about the whole thing is, if you buy animals in poor conditions from the pet stores, you are encouraging the practice of not taking care of the animals properly. It doesn't matter how many animals you "save" from the pet stores, there will always be more to take their places in the same cages, fish tank, shelves. I see no point to "rescue" poor animals from the pet stores as it will only bring the pet stores profit by continue doing what they are doing.
What does everyone think? Would you rescue a pet from the pet store if you see it's in poor conditioner, and perhaps already sick?