I said before that I dont buy in for a second on that "some people register AOA but dont mean it" nonsense since it realistically cant be a lot of people per school but is probably about the same amount of people per school. And the people who do it are either taking a big risk of matching into something they dont really want to match into, or are wasting their time and energy (and money?) applying when they 1) dont intend to match and 2) wont be able to use that scramble list 30 days after its released. Not given the number of people scrambling who are legit about it. I just dont see "applying but not intending to match" ever happening.
Many of these people are likely intending to match ACGME. To have the fallback of an AOA transitional year, you must be registered for the Osteopathic Match. However, given that matching AOA pulls you out of the running for the ACGME match, one who is gunning for an Allo spot will rank no Osteo spots, thus leaving the possibility of such a fallback.
As TrueBlueBlazer has correctly stated, many transitional programs wait until after the ACGME match to fill their posts hoping to snag well qualified candidates that just didn't happen to match in the Allo world.
Check your facts before slinging your personal opinions.