It's in there, because at some point in the build script, everything that's left in /usr/local/bin is assumed to be intended for development, like qmake, etc.
I'd rather like to move qtconfig into another package, but since it depends on qt-4.x-sql, qt-4.x-xml, and qt-4.x-qt3support, I'll have to agree best thing would be to move it into an own package.