Not sure what you have seen with your "own eyes," but no US forces still use the 30-06. It was replaced in the late seventies in individual and crew-served weapons by the 5.56 and 7.62. US snipers have used the .300 Winchester Magnum (along with the 7.62, .50 cal, etc) in recent decades, but not the '06. It is no more a "military" round than the 7x57 or 8x57. And I would agree with others, the '06 is significantly more versatile than the 7x57mm.