Are there other places like this?
Why Georgia?
Elbert County Georgia bills itself as the “granite capital of the world”.
Drive thru the town of Elberton and notice everything made out of granite.
Some people around there put granite monuments in their yard.
Some are fun, some are serious.
I put them in the same category of unusually painted barns.
I attended Flag day celebrations in Elberton for many years in a row in the 1990’s. I was one of the ones who jumped in and flew a flag from my parachute as entertainment.
You might guess the event had political overtones ;)
Just normal folks who happen to have a granite industry handy for expression.
They are blessed with many Purple Martins also and Purple Martin gourd houses are all over the place.
Just some perspective.
The message cited in the OP is wierd.
The medium (granite) is not wierd for Elberton.
Might be connected to the people who named the city of Atlanta. How might the name be connected? Research the name.