I ordered an iPad 2 along with a Smart Cover from Apple's online store when they became available years ago. A couple of days (IIRC) later I decided that I wanted Apple Care for the iPad 2. I went online to see if there was a way I could add that to the order, but there didn't seem to be. So I called to talk to a customer service representative to see if there was any way to add it, considering that my order had apparently not shipped yet.
The representative told me that she couldn't add Apple Care, that I would have to take the iPad 2 to an Apple Store to have Apple Care added after I received it. (I could have also canceled the order and reordered the items I suppose, but if IIRC the shipping times for the iPad 2 had gotten longer since I placed the original order.) I lamented that the nearest Apple Store was more than an hour away from me, but suggested that was probably what I'd do and thanked her for her assistance.
She expressed regret that I'd have to travel that far and said that she was going to credit me for the cost of the Smart Cover that I had ordered (IIRC it was $39). I was quite pleased with that gesture of goodwill, especially considering that Apple hadn't done anything wrong to create the inconvenience. It was I who decided after placing my order that I wanted something additional. Also, it wasn't like she was just offering to give me something extra that I may or may not really want. I was buying the cover anyway, so the gesture represented a real savings of about $40 for me.