Ethical De-Cluttering

Lately I've been thinking a lot about simplifying my life and reducing my possessions. I even want to move to a smaller place to encourage my husband, C, and I to accumulate less stuff, but that's not economically sensible right now (we have a really good deal on our rent - so much that we might even pay more if we moved to a smaller place).

One question I've been thinking about is whether or not it's ethical to return something that I've used but decided that I don't like to a store with a good return policy such as Bed Bath & Beyond or Costco.

I know that both stores will accept returns of used goods with a receipt or proof of purchase. Am I just taking advantage of these stores' generous policies or am I abusing the system? I've used these items on a handful of occasions, but probably less than 5 times in the year or so that I've owned them.

I'm still thinking about this. Of course, I still have some unopened items from these stores that I'm planning on returning.