I ran across this thought-provoking article in the Blog called "Genealogy's Star."
I never thought of the possibility of the information on grave makers being copyrighted. The author of the piece, an attorney of many years, gives his opinion on the subject. The bottom line is, in his opinion, that since the information is in the public record it cannot be copyrighted, but the issue has never had the scrutiny of a court case, either.
In the article, the author refers to another, related incident that has been making the rounds in genealogy Blogs: a church that prevented a person from publishing information from grave makers located in that church's graveyard for "privacy" reasons.
This all has the characteristics of a "tempest in a teapot," but you never can tell how much energy it will really gain. You can read about all of this at the following website: http://genealogysstar.blogspot.com/2009/03/no-copyright-for-gravemarkers.html