We're very different DMs. A couple of months ago I wrote a blog post on how random encounters changed the trajectory of my campaign. Just like the players, as a DM I enjoy the suspense of finding out what happens and the challenge of reacting to an unexpected obstacle.
This I would also say, that we have different mastering style. Probably due to the "bit of narrative style" our table includes into our gaming (all DMs at my group do this - to a varying extent).
The suspense for the players you can create by an unexpected move of the antagonist as well - without consulting a single random table. Yes, I admit random table are a pretty awful thing for me ;-) Don't like them.
But maybe we should leave the discussion at this - to avoid just repeating us ;-)
The advantage is exactly what I stated in the quote. Randomized encounters often result in situations that I normally wouldn't think of. They get me out of my comfort zone and keep me from falling back on my own personal tendencies and my own personal motivations.
Getting the players out of the comfort zone is a good idea. The way to go, I would say. You can do this without a single dice roll.
External stimulus is also a good idea. Here it is very nice to let players tell what they WANT. Either describe an "open" situation where the players can define some elements of the story as fitting for their characters (I use this only as session-starter) or by letting a player do a suggestion (like: "The camp in front of us - that's actually the army, I think!"). And then let him roll. If the roll is good, it is as he says, if he rolls bad - come up with complications. If it was really bad - serious complications ("Yes, it is the army - but the other one, the one that's hunting you..."). Okay, the examples are a bit lame right now.
We actually had one of our GMs experimenting with random encounters some while ago, the comment of all involved players was that it
was not good GMing to include "boring enemies with no focus on the story, and who felt like totally uninteresting - you surely can do better than this". All agreed on that.
Note the opposite of random encounters is NOT pre-planned encounters - which are as bad. It's just that you use the antagonists - and henchmen - available in the story and when the situation for an encounter arrives - use them.