The only times when I ever had wet dreams were when I went a long time (days? weeks? I'm not sure now) without otherwise ejaculating. I had two or maybe three of them. I remember clearly that in at least one case, the content of the dream had nothing sexual about it: in the dream, I was trying to blow some stuff out of my nose, and when I woke up, that turned out to have been my ejaculation! It was a nasty dream and a nasty awakening. So don't assume that wet dreams are fun.
(Added in editing

I think that the reason why most posters in this thread report not having had wet dreams is that hardly anyone any longer goes without either having sex or masturbating (or both) for long periods of time.
On the other hand, if you shoot like Peter North, maybe only a few days without ejaculating would be enough to cause a wet dream. I expect that if he had a wet dream and slept through it, he'd wake up to find himself glued into the bed!