There is a Petco here on Long Island, the one on Old Country Road that has a good saltwater section and the corals are healthy and thriving.
They have a guy, his name is Jeff I think, that works in that department that stepped up and got the store to get the right lighting and equipment for the saltwater stuff.
I have purchased, watermelon zoas, pulsating xenia, midas blenny, green bubble tip anemone, emerald crabs, snails, and electric blue goby(not sure if thats what its called) from there and they are all still alive healthy and thriving. He woudnt even sell me a green bubble tip once bc he wanted to keep it in their system a bit longer to see if it was thriving and healthy since he only got it in the day before. Its only my opinion but I was kind of impressed for a Petco bu I guess its all about the employee though who has a passion for it and its not just a job.
Surprisingly some fish/coral and inverts Ive gotten from other salt water dedicated stores in the area havent lasted or thrived.