In purchasing a book today, I thought I needed to click "Add to Cart" to make the coupon work (of course, I don't, I need to click "Update Cart.")
On clicking "Add to Cart," a resource was added to my cart. I finally figured out that it was from my wish list.
This is unexpected behavior. It would expect nothing to be added, if nothing is selected.
Here are a couple of screen captures that illustrate the issue.
Before clicking "Add to Cart:"

After clicking "Add to Cart:"
