I would consider NQEs the closest thing to regional championships, but people don't generally treat them as such, I suppose.
USA Dance comps not all one-day comps, and I think many students actually prefer one-day competitions because they have homework to catch up on all the time. If you are a USA Dance member, then competitions are well-advertised through email. I think more collegiate competitors are aware of USA Dance competitions nowadays than used to be the case, but it tends to be the higher-level dancers who find out about them and are willing to pay more for what is often a higher level of competition (especially because many competitions do not offer pre-bronze/newcomer). There does, however, need to be that tipping point of number of competitors to be appealing. For example, Midatlantic and Manhattan Amateur Classic are very well-attended, but the midwest ones seem pretty small. One very nice benefit of USA Dance competitions are scholarships offered, at least for certain events. At least in the Midwest, very few collegiate competitions provide scholarships, only those ribbons we symbolically covet so much.