"Does it ever" seems more abstract than "Has it ever".
"Does it ever snow in Sydney?" seems like it should be answered "Well, it has, but most of the time...". I presume the question is more about the nature of Sydney than what kinds of historical accidents have happened to Sydney. Answering in a present tense, "Yes, it does", seems to me to imply some measure of regularity, and for truth and justice one should modify the answer with a "sometimes" or "occasionally" or "every damn day this winter fr goawdsakes". By comparison, "Has it ever snowed in Sydney?" is obviously a yes/no question. Similarly, "Can $12 million ever be justified?", I reckon, should be answered, "Well, yeah, this one time it worked out great, but... [pros/cons/issues/etc that apply to other times]"