Came across this quote this morning, in a piece written by Viktor Shklovsky called "Five Feuilletons on Sergei Eisenstein," (a bit of a pet project of mine, too-- Eisenstein, not feuilletons) in Context:
"Artists have certain freedoms when they draw from real life: they have the freedom to choose, they have the freedom to change, and they have the freedom to offend."
Sums it up pretty well, I think.
Context is great, if you haven't checked it out yet. Their entire backlog is online, too, filled with excerpts from Dalkey Archive titles and essays from and about Dalkey authors.