That is scary stuff!
Years ago, there was a flight attendant who checked into a hotel. The clerk gave her the room number out loud and a man who had been following her who overheard.
He ran up the stairs to her floor and when she put the key in the lock/used the keycard, he pushed her in the room and spent the entire night sexually assaulting her and stabbed her over a hundred times. (There was a Dateline or 20/20 episode on this.)
Now, hotel workers will not read out your room number when you check in - they point it out on your card and close it so no one can see. If someone reads your room number out loud, demand another room.
When I flew, I was always overly cautious - there are other horror stories with hotels. Now, they are putting homeless, illegals and other unknowns in hotels. Be careful out there.