Should rhetorical questions end with a period?

Would it be appropriate to end a rhetorical question with a period, to show that it is not intended as a question that one should ponder or attempt to answer? For instance:

Why do I eat so much(?)(.)(!)

I don't want anyone to answer it, but it's still phrased as a question.

Solution 1:

Rhetorical questions can be ended with either a question mark, an exclamation mark or a period. Using a question mark is probably the most common choice, but it is really up to the writer to use whatever punctuation matches best the intent of the rhetorical question.

Yahoo's styleguide, which I would not consider as a reference, gives some examples of such usage:

• Can you believe it? I just bought that car, and it’s already scratched.
• What kind of a man are you?
• Boy, do I!
• How can you possibly think that!
• Would everyone please rise for the national anthem.
• Why don’t you stop asking me questions already.
• Why don’t you take a long walk off a short pier.

As for my personal style, I don't use rhetorical questions much, but when I do I end them with question marks.

Solution 2:

Rhetorical questions are written as any other question, and in English a sentence is never ended with a question mark and a period, even in the case the question is being quoted.

I have never seen a question mark followed by a period to mark the question as rhetorical. It is the context to make a question rhetorical.