I have not heard of it at BS in my circles. My guess is that there are several things at play.
The CCs make the expectations around ED quite explicit. They explain that the current students are the beneficiaries of those who came before them and followed the rules and that they owe the same to those who come after. These schools are not big, and they have tight communities. It’s pretty unlikely that one could default anonymously.
College counseling is thorough and starts early - more as picking the best courses for emerging interests and evolving from there - so by senior fall, most students have enough clarity around their preferences that they don’t need to ED to a “wrong” school.
Over the years, I have seen some unusual changes of plan by athletes from all types of high schools - from one D3 commitment to another when a coach moves, from a D3 to a D1 when a roster spot opens, etc. I don’t know if the original D3 commitment was ED or if there were caveats to the agreementto attend as athletic recruitment is its own beast.