Absolutely. They are among the most notorious when it comes to ghosting applicants. Just one of the many charms of the so-called sellers' market. Unfortunately for us, due to the intense competition, there is really no reward for the good guys or penalty for the bad ones, so we are totally at their mercy. Which is very ironic when you think about it, because they all preach humanism, ethics, morality, etc., and then some of them turn around and abuse their market power to treat their customers like absolute crap.
P.S. Based on my research, I fully expect to be treated exactly like you. Even so, I chose not to spite myself and to take my shot and apply. I will admit, however, FWIW, I am not prioritizing returning their secondary. I'm sure no one in South Beach is losing any sleep over that, and I'm not doing it as a silent protest, but I am devoting my attention to where I expect the biggest bang for my buck. As a result, I am making every effort to impress those schools that don't treat applicants like crap by turning their secondaries around as quickly as I can. Miami, with its never ending series of questions, will wait, as I'm certain I will wait after I submit.