Collecting Children's Books has had a couple of interesting posts about books such as They Were Strong and Good and The Rooster Crows, which have been bowdlerized to reflect changing standards of "appropriateness" in regard to depictions of nonwhite characters. Those are two among several if not many; Mary Poppins, Charlie and the Chocolate Factory and Dr. Doolittle are some of the others. What I hadn't realized until Peter pointed it out was that changes like these are sometimes made without any acknowledgment of the fact within the new edition; kind of Orwellian, yes?
Many years ago I was on YALSA's (then YASD) Intellectual Freedom committee, and we had a bit of a tussle with Scholastic, which was asking authors to make "word changes" (read: remove obscenities) from their books before Scholastic would reprint them for its lucrative book clubs. Two things were at issue: Scholastic did not want to acknowledge, in the paperbacks, that changes had been made, and, in the cases of books that had been named to the Best Books for Young Adults List, the publisher wanted to be allowed to say that the expurgated editions were BBYA winners. No and no, although we only really had the power to enforce the second.
To me, the weirdest part of Scholastic's argument was that since it was the author making the change, an affected book was still a BBYA choice. And some committee members bought this argument, as well as buying into Scholastic's emotional blackmail that we were "punishing the authors" by disallowing the BBYA designation. Well, tough: why would we want to reward authors for caving to commercial pressure? The money would have to be enough.