Some stores are open all night but not any pet stores that I have ever heard of. It wouldn't make any sense. There are not many people (besides fish fanatics) that get an urge to go pet shopping in the early morning hours!
Chain stores close later than privately owned stores, but the latest is 10 pm.
However, if one were to go to a store like walmart (is it a department store or what?), they may be open 24/7, but their staff and stock aren't very reliable.
You guys have given me a great idea. I wanna open the first all night fish store. For emergancies and stuff.THink about it, what the heck would you do if your tank sprung a leak or something. Chances are you fish wouldnt make it through the night unless you had another tank somwhere. Lets go one step futher. Your tank goes. You have an extra one but are completely out of aquasafe, because you didnt plan to do a water change till the weekend anyway. How would you fill the new tank without water conditioner? I know youd come on down to fiddlesticks all night fish emergancy store.
You had better make that a chain store, otherwise Fiddlesticks all night fish store better have supersonic delivery capabilities for those around the globe.