And to add a little more color to Joe's comment, the NTIS regional event coordinators actually pay USA Baseball to host those events in a territory. It's very much like a franchise. I'm very good friends with someone who runs a large academy in my area and he was approached by them about being a host site. Once he saw the price tag and how much he'd need to generate to get above water, he respectfully declined.
I would say that if you get selected from a regional event to Cary (which you also have to pay to attend), it can be a very cool experience. Much like attending a college camp, going to Cooperstown, or any other youth baseball experience. Just like those, know that it is a pay to attend event and that the road may very well end there (or at the regional tryout). You need to weigh for yourself if it's an event/experience you're willing to pay to for your son to pursue.