+1 to the paranoia. Unless I take on a career as a CIA spy, I probably won't worry all that much about evil-doers trying to get into my hotel room.
Theft of stuff? Yes, I take basic precautions to prevent the housekeeper from boosting my laptop or Kindle, either not leaving the stuff there or putting it in a safe. Crazy-expensive jewelry? I don't travel with it in the first place. The deadbolt/latch? Yes, I use it when I'm in the room to prevent a hotel employee or double-booked guest from walking in without me knowing about it.
Fake friends to fool enemy espionage agents?
Uhhh, no, haven't deployed that one.
Other bad practices I have: I often walk through the hotel with headphones on...if I'm on my way out for a run. I prop the door open to get ice, leaving a solid 60-90 seconds for a cat burglar to determine that I don't travel with expensive jewelry and my laptop is a 3-year-old piece of crap, a big heavy brick hardly worth the effort to haul it off. I don't exactly advertise my travels online, but I don't actively take steps to conceal it. If I meet up with friends to catch a game or whatever while I'm traveling, a tagged photo might end up online. I don't care. I've booked tours through a hotel, leaving open the possibility that hotel employees know my room will be empty all day.
I guess I'm just rollin' the dice, right?...
I get that there are parts of the world where very location-specific security measures should be followed (although those tend to be deployed more at the perimeter of the hotel property and outside the grounds than in the room itself). But I find a lot of the tips to be a bit overkill when we're talking about the Tulsa Marriott or whatever.