Costco's doing it right
Initially people swarmed and some bought way more than they needed of TP, cleaners, rice, formula, etc.
Wiped out all the shelves so people wanting to make normal purchases couldn't.
Later as stocks started coming in, many of the stores restricted people to 1 per.
Now that shelves are filling up, some people want to return what they hoarded.
Costco and other stores are saying, "Nope, don't want it back." And good for them.
I don't care if you were buying for a school, church, your friends and family, or because you thought you could make a buck while people were in need.
If you bought too much either because you panicked or because you're greedy, no one wants you returning your potentially virus infected stuff.
You bought it, it's your problem now.