You are correct, pet stores, Petsmart, etc. do not change their water parameters, for anything, they also do weekly water changes (or should do) and generally the people in those beginner pet places barely know anything...

What most people do not know is that the breeders don't do not change their water parameters either... the more chemicals you dump in your tank make it harder on your fish, with the ups and downs in pH and the like, I to have found fish are happy when you do frequent water changes. People do not believe me when I tell them how long my fish live (recently lost my oldest fish my mommy corycat that was over 10 years old – she had a good run)

The only exception I make is when you’re setting up the tank and water changes, I use the cycling aids like biozyme help a bunch, salt and de-chlorinator.