I don't see the amphitheater thing working out to well in st Tammany
It does seem kinda weird, but here is my reasoning:
Most sheds are in suburbs of major cities. Alpharetta (ATL) Pelham (BHam) Maryland Heights (StL) Columbia,MD (Baltimore) West Palm Beach (Miami) The Woodlands (Houston) Chula Vista (San Diego) are all examples of this. Why they do it like this I don't really know, but it seems to work for the most part. I guess space is a key aspect.
Another reason is what CitizenKane said about the ground itself and the surrounding geography. St Tammany is much higher than the south shore.
Either way, I don't really care where they build it, as long as it somewhere in southeastern LA. It is part of the reason we get skipped on by so many bands. Plus the season for an amphitheater in Louisiana could be very long due to the warm climate.