Basically, the company has physical stores and also sells stuff online. Stuff bought online can be returned in store. However, if you bought an item online which was on sale, you could return in store for the full amount. I returned a laptop which I bought online for $999 and received $1399 back.
I think it was due to the fact that the store runs on iSeries/AS400 and the website is in .Net. I happen to work with both, and I can imagine that there is a lot of pain to make the systems work together.
If they didn't bother to look at the receipt for your laptop... well, that seems like negligence on the part of the staff handling the return.