From what I know about how schools work, it’s very important to them that they not “collude”, so no, it is highly unlikely that they would confer about applicants.
They might make assumptions about where they fit in your pecking order and not admit you if they have picked up that they are at the bottom. For example, if you are a fourth generation legacy at another school, you should have a good reason for your interest in the school (and it’s not that hard to come up with one) or they might pass on you figuring that they’d just be wasting their acceptance on you.
There is one caveat – if you are applying through a program (like ABC), it’s not unusual for the program coordinator to convey to the schools how your choices are ranked. In those cases, you may not be admitted to your lower ranked choices if you are likely to be successful at your higher choices. Iow, you don’t lose out because you are accepted to your top choices and the schools you aren’t wild about can admit students who want to be there. (This works well for the programs too because they get more students placed.) For most applicants here who are applying on their own, this scenario won’t apply to them.
But please understand that the schools aren’t focused on yield because they care about the number itself. They are trying to manage enrollment and to create a class. Every student who goes elsewhere is one they thought would bring something to their community and who now risks creating an unbalanced community - too many girls, not enough musicians, too many local kids, etc. So if you look like a good fit to them and that your interest is genuine, you really don’t need to worry. Look at the results threads from prior years and you’ll see quite a few kids who had a number of good options.