When we put in our initial service selection preferences Plebe Year, 70% of my 1200 Midshipman class put NA as their #1 choice. Over 50% put it #1 in their final prefs Firstie year (I know there were even more who wanted it, but knew they weren't going to make it and put their #2 choice as #1 to have a better shot at not getting #3).
So, yes, there are people who want those other service selections, for sure. There are many more who get told to take their 2nd or 3rd choice.
What I've been told from USAFA types is that it's a major philosophical difference. It's pretty much like everyone starts out with pilot as their presumed selection, then they let medical whittle it down, which takes care of most of the overage. Grades and class rank soak up the rest. Maybe a Zoo grad can weigh in here with firsthand to back that up.
As stated earlier: the prevailing sentiment regarding getting pilot at USNA is
These days you need to be a total a$$ kiss with a 3.3+.
I guess what I'm saying is, based on what I've seen, heard, and read, if I had to make the choice again and
all I cared about was flying something, I would not choose USNA.