I have only rescued one from Petco, but I see them every week. I would need a wall of tanks to do what needs to be done. Half the time I go into the store just to beg the managers to do a better job and point out the fish who really need help.
Didn't get a before shot because I was in too much of a hurry to get him out of the bad water and keep him alive. He has the most personality of all my boys.