In reality it makes as much sense as having two centerfire in any two mid sized cartridges. In other words it makes as much sense as having a 308 and a 7x57. As looneys we want a wide variety of incremental change in the firearm itself. We should be buying rifles based on the game available and that we may encounter. In North America we have only 4 really large big game animals bison great bears moose musk ox and not 1 in 100 of us will even hunt them. The rest are non dangerous ungulates that can all be taken reliably with any mid sized cartridge from 24 to 30 caliber .
Which is why years ago, in a lot of households, there was just one .30-30 sitting behind the kitchen door. But still....
