One way that this problem is being attacked from the other side is that certain prep schools have a policy that if you’re admitted early somewhere (except for a state school with rolling admissions), whether or not it’s early decision, you can’t apply anywhere else. The prep school won’t send out any more transcripts, recommendations, etc., once you have an acceptance in hand. The only exception is if the financial aid is inadequate (generally less of an issue if the student is already attending private school, of course). Effectively every early application is an ED one.
This significantly reduces trophy hunting among the population at these prep schools (generally, once you’ve got an offer, you aren’t getting any more) and, importantly, enables the guidance counselors to assure the adcoms at the colleges that if they admit a kid, he’s virtually guaranteed to matriculate, which is a valuable advocacy tool.
The kids and their parents who are aiming for HYPS (which all have early action programs) don’t like this, of course, because it forces them either to (i) make a clear first choice or (ii) forgo the undeniable statistical advantage of applying early. If every high school were to handle things this way, though, the process would become less insane, it seems to me.