As far as the small business return policy, I think it's important to remember that small businesses are going to run differently than the big ones. Their policies will be more strict, they will allow less exceptions, simply because they have to. Expecting a small business, mom and pop store, to have the same return policy as a major store is being a little unreasonable. Because they're independent, we can't assume that what goes at Target goes at the small store. I think people forget that because they're so used to shopping at major retailers who have generous return policies.
LOL, this made me laugh, because the one and only time I've gotten annoyed about a return situation was with Target. Actually avoided them for years as a result. And what made me so irritated was that they ARE a big chain, so...
Don't know if the return policy is still the same, but... back when we got married, we registered at Target. We put an ice cream maker on the registry.
Well, my MIL bought it for our shower. But somehow it didn't get taken off the registry. (Don't know if that was MIL's fault or the store's.)
So then sure enough, months later, someone bought it for a wedding a present.
We are close to my MIL, so even though she'd bought us the first one, we asked her for the receipt (explaining the situation). Did not want to ask the wedding guest, seemed too rude.
So there we were... two ice cream makers, one receipt that was about three months old. We didn't ask for cash, we asked for store credit.
Nope, they wouldn't take it. We had to have a receipt dated within 30 days EVEN for store credit. Nevermind it was in the box, never opened. Nevermind they still stocked it. Nevermind it was on our registry so they could check out that umm yeah our story was probably true. Nevermind that we had a receipt from three months ago. Nevermind nevermind nevermind.
We were pretty low-income at that point in our lives so the fact someone had spent this amount of money on us for an item that we couldn't use because we'd already gotten it (seriously the ice cream maker was the MOST frivolous thing on our registry, everything else was pretty cheap and basic stuff--measuring spoons! LOL) was really disappointing to us. And I WAS annoyed at Target and will always remember this, specifically BECAUSE they are such a large company it hardly seems it would have hurt them to take back an item they could restock and resell immediately and give us store credit instead. And a store credit would have helped us out on some necessitites of life (socks, underwear kinds of things) for a while--would have really helped us out on our measly income at the time.
Now, my own rant aside on Target...
OP, it's a coffee mug. Trust me, given my own experience that I just ranted about, I know how emotions can just bubble up over something like this.
But truly... to ask for a refund or exchange without any receipt is asking a lot of any business. They have no way of knowing whether the item was stolen.
We used to exchange gifts with my husband's entire paternal family. Every year we got stuff that we just don't use. But you know what? So what. People cared enough about us to shop or create something for us. It's the thought, not the gift.
Hope you have a nice New Year's.