Of the limited 14 Fall students I know, there are at least 2 also got offer from NCSU PhD. Now they both got admitted to Booth.
If you have professors at NCSU that you are particularly interested in, just go ahead. Give it a visit. At PhD level I think, it's more about your advisor.
For the "cash cow" issue, I think the 25% tuition remission for everyone says something about it.