Sean - AHA! Ok, that makes sense to me. An internal practice area that really is a boundary of the course - we can think of this like the MANY courses here that surround housing tracts. In the great scheme of things OB like this might be called "internal", but a better way to look at it is it definitely marks a boundary of the course.
I have little issue with that.
I too despise the type of internal OB that just separates two golf holes, for whatever reason... Good lord, at my beloved home course Santa Teresa holes 2-1-9 are all adjacent to each other, all with OB on only one side which "counts" in only one direction! That is, 1 is in the middle, with 9 on it's left and 2 on its right, each being played in the opposite direction of 1. There are stakes on both sides of 1. BUT.... shots are OB only to the left of 1, right of 2, left of 9. It's silly and stupid, necessary for safety issues only because the course is constantly packed. I hate it and have never gotten over feeling that it's a definite weakness of the golf course. It is rubbish in general and specifically here. But I guess they did the best they could...