All I can think of is that it keeps the door number down to one. A 20-24 inch wide door is max , but better to the eye then two 12" doors on the same piece, and half the hardware. So, a 24" door with 6" aprons/stiles on each side can handle a 3' wide cabinet.
I've a few Shaker Designs I've built that have this feature. One, I was sitting in my LR reading during a humid summer and heard a BAM, Door blew apart from my neglect . Just hard to allow enough movement for a 20" plus door panel. Fixed that. Now, the same piece shows that 6" side cabinet stile/apron detaching from the shelf it is attached to. 6 inches is enough to noticeably move and it will not be stopped by any means. So. I'd suppose that the original Shaker Designs might not do so well in modern heated homes. Nothing wrong with pieces that age and wear, that don't look new but still function well. Just be sure to apply a finish that is close to the natural wood tone. In my case, I used a black milk paint that looked so good , but every breach of a seam means I have to repaint, or touch up .
So. it's a look from a time gone buy that many of us appreciate. Just expect that , in a few years time, it will show some signs of wear and of modern day wood movement