I am sympathetic to OP's bad experience.

But I saw it from the other side last year, in Bergen, Norway. We had no reserved room, but found ourselves back in town due to a train incident that blocked the tracks (we were stuck in a tunnel for 4 hours). We had not planned on staying in Bergen for a second night, but had a sleeper booked on a later train that could not operate. The hotel we had stayed at the night before was fully booked when we arrived at midnight (exhausted), but found us another hotel that, while fully booked, also had several no-shows. After 15 minutes of deliberating, the second hotel called back and let us have one of the no-show rooms.

We were very grateful!