You make valid points. I believe the contradiction here lies in the exact context. The individual shop employee might be "unable" to issue a refund, due to the

You make valid points. I believe the contradiction here lies in the exact context. The individual shop employee might be "unable" to issue a refund, due to the policy set in place by the managers of the shop. The shop as a whole is certainly able to change the policy and provide refund (unless it is out of money, of course). The individual --- phrasing the message --- might be accurate. But the customer is not interested whether the person in front of him is able to issue the refund. He is usually interested in getting the refund from the shop as a whole. Similar arguments apply to the Google store the person or more likely the software system that composed that email might be unable to reinstate the account, but Google most definitely is. But Google is merely unwilling to do so.