Dude is a flying, well, walking symbol of hope and good.
He wears the shield and dons the cape - and the underwear over thights. That may be called flashy.
He is supposed to be a humble man, and that does not call for rude or tactless comments. If he does not want to comment, simply reply 'no comment', no point in answering like an obnoxious jerk - that was not humour, that was rudeness in his words, and Clark Kent was raised better than that prior to the New52.
NO, I'm honest, I agree with you, I'd only include comments about how famous and relevant Superman is and, if he is doing something so out of the ordinary, there must be a reason, even though said reason, as given, is practically non-existant and badly written, as Linkara presented. I agree, people should just leave SM in peace...
BUT the fact of the matter is, he IS a big piece of news, and his walking around IS a big deal of strange news. It is not like saying, "Oh, the mayor is walking around his town", this is more on the lines of "Obama decided to take a walk around Pennsylvania", that's how out-of-the-ordinary this is and how he should not act like a douchebag for an ordinary reporter making a legitimate question.
If he is not flying, he should not say "because I'm walking", that's a total lack of education and tact from a character raised as one of the very, very few polite superheroes ever.
So it is not an "agree to disagree" scenario, more like "yeah, I agree partly with you, but there IS another side of this whole story that I agree more".