@ DiedrichVK My best guess, given the evidence, is that it's because he does not understand the concept of a rhetorical question, which in Japanese, often ends in "ne". On top of that, he refuses to (or simply does not) realize that it takes a restructuring or rephrasing of the sentence in order have it actually BE a question instead of a declarative statement. To him, if it ends in ne or ka, that means you put a question mark at the end, and damn the context, full speed ahead!
Yes, I realize I'm answering a question from 6 years ago, but now the answer exists somewhere.