"None of your daring scintillations here.

As to why I don't do it in private, I rather fail to understand your question.

The answer is of comparative limpidity.

I don't do it in private, because it is funnier to do it in public.

You appear to think that it would be amusing to be dignified in the banquet hall and in the street, and at my own fireside (I could procure a fireside) to keep the company in a roar.
But that is what every one does.