Finally, at around noon, she is told we can get into one room, and she temporarily has us all put our stuff there. A couple of hours later, we find out the room was double-booked, when an indignant mother of pre-teens comes in, expecting that it's her hotel room. Both she and my group leader (whose credit card paid for the rooms) are upset. When she goes to the front desk to complain, she discovers that the hotel has given both our group and the other lady's group new rooms. I don't know why they felt the need to do this, but there were guesses that the hotel didn't want to seem like they were playing "favorites." Whatever.
However, at this time, she is also told that our room will not be ready until 4. And while this is not a huge deal, it was a very large inconvenience to be told that because the hotel made an error, we would have to move all of our things, and our second room, which we had already paid for, would not be ready on time.
Edit: Right, okay, we messed up. I do honestly get that now, thank you, though I still don't believe it's beyond my ability to be annoyed at the hotel. You can continue to tell me, but I don't really think I'm going to read every single comment (since the general gist is: don't do that). In the future, we'll be more aware of these issues.