TCM prints and opening titles

So I watched The King's Vacation off of my DVR last night. It's a George Arliss movie not on DVD about a man who never really wanted to be king who abdicates when revolution comes and tries to go back to his old life.

But that's not the reason why I write about it. I noticed that this was another of a bunch of early 30s movies I've seen on TCM where there's something odd with the opening titles. Since all these movies are in close to 4:3, they're pillarboxed on TCM, as opposed to, say, FXM Retro, which just stretches the old movies to fit a 16:9 screen. (Yes, I know the Academy ratio isn't exactly 4:3.)

The opening titles, however, are different. They're pillarboxed and slightly letterboxed. The King's Vacation is by far not the first movie I've seen this done to. Anybody know why this might have happened? I can't think of any particularly good reasons for it. If something had been done to the entire movie, that would be one thing, but just for the opening titles?