WIST

Wanting to meet an author because you like his work is like wanting to meet a duck because you like paté.

Margaret Atwood (b. 1939) Canadian writer, literary critic, environmental activist
Negotiating with the Dead, ch. 2 “Duplicity: The jekyll hand, the hyde hand, and the slippery double” (2002)
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Usually directly attributed to Atwood, but she made it clear that it was not hers:

There's an epigram tacked to my office bulletin board, pinched from a magazine -- [the quotation]. That's a light enough comment upon the disappointments of encountering the famous, or even the moderately well-known -- they are always shorter and older and more ordinary than you expected -- but there's a more sinister way of looking at it as well. In order for the paté to be made and then eaten, the duck must first be killed. And who is it that does the killing?