Kansas University runs a similar camp. Our kid received an invite after attending the Stanford camp. Looks like KU used the Stanford attendee list as a mailing list. Most of the schools at the KU camp were also at Stanford, including Stanford. A couple Big 12 schools not at Stanford were at KU.
Our boy might have gone, but we ran out of showcase money. If I had to do this again I'd still pick Stanford as #1 recruiting camp to attend.
Word to the wise - your player's grades need to stack up to Stanford admissions requirements to ensure an invitation.