Honesty is the best policy.
The customer service goal for world-class organizations is to not only satisfy customers, but to delight them.
That isn't rocket science, that's just Retail 101 and it has been for the last century.
There's a perfectly ordinary chain drugstore in my town, but I'm their customer for life, because they just do everything right. It's nothing that grabs you in particular. But the advertised specials are always there. They put more people on the cash registers the lines build, nobody greets you obtrusively when you walk in the store but when you want help you get it. All the silly little retail things you take for granted. Nothing special, nothing they shouldn't be doing, it's just that they do it all the time, every time.
And they always do the right thing on returns. Whether the package is opened or not. Whether you have the receipt or not. Just because you say you want to return it.
Returns matter. Customers worry about buying the right thing or getting a lemon, knowing you can return something makes you more likely to purchase. Returns are unpleasant; you always fear rejection. Returns are especially important with gifts. The best way you can convince someone to buy that gift is to convince them that it's easy for the recipient to return it.
Best Buy? I don't think they're such an awful company really, but the time I tried to return a cheap DVD player that just plain didn't work and they hit me with a restocking fee, I got a cold prickly. I wasn't going to fight them about ten bucks or whatever it was, but it was just plain wrong, they shouldn't a done it, and I remember it. Do I still shop at Best Buy? Sure. But do I love the store? No.
Accepting returns graciously, quickly, and efficiently is one of the best ways a store can build loyalty. Best Buy is screwing themselves by getting a reputation for being difficult on returns. It's the kind of thing that spreads by word-of-mouth. "Don't buy stuff there, it's a hassle if you need to return it."