What you have asked versus the example that you gave are 2 unrelated things.
Some good answers have been posted about your example. Personally I believe that, as an earlier poster mentioned, segue pretty much "hits the nail on the head".
However, your question is not talking about this at all. To relate your example with your question the respondent would need to say something like:
"That's a dumb question" or "Your question has no merit" or possibly responding with the rhetorical question "Why would you want to go to McDonald's anyway?"
In all three of these cases, you have posed a question and the response is a premise without argument (indirectly in the case of of the third example response which is a rhetorical question or in other words a question that expects no response and is merely trying to assert a premise - that being that your question shouldn't be asked).
In the world of logic a premise on its own without arguments leading to a conclusion that supports the given premise is laughable and shrugged aside. It is a symptom of a lack of understanding, ignorance or foolhardiness.
The person is acting as a demagogue attempting to get their point across not by reasoning rather by volume, repetition, or in this case mocking you or interposing a premise in an effort to block your query. I can't think of an idiom that exactly matches your original question. It is close to tautological reasoning but that doesn't quite cover it.
To me, it exemplifies ignorance. The person should lend a little more credence to "no question is a stupid question". Of course, one thing someone who deals in premises without reasoning would probably do is take "no question is a stupid question" and apply another logical fallacy "Reductio ad absurdum" and come up with a ridiculous question to prove that there is such a thing as a stupid question, completely ignoring the spirit of the above idiom.