We don't want to eliminate the variety of the sport. At least for me, that's the fun of it. If it's not, then it is just a discussion of utility and we don't "need" any of it. As long as we have grocery stores, a military and a police force we don't "need" a firearm. If we are waiting for just in case ... whole generations have died off waiting on that. It's like owning your own fire truck in case you have a fire. We might as well join the liberals and get rid of them all.
If you look at all those countries that have lost their arms, they are living and breeding just fine. Gradually taking over the world. I don't want to be them, but they are still thriving.
Our ancestors did just fine with whatever muzzle loader they could find and afford. When it comes down to it, we don't need all of these cartridges. There is nothing that can't be done with a .30-30. It's even more versatile if you hand load. You could make the same argument with a .357, though at a shorter distance.
So, although I like and own a lever in .357. I can load a .327 just a bit cheaper, and I can take a deer or a coyote with just a little less meat damage. And if I want to hunt groundhogs or coyote, I will feel better served with the .256 Winchester or even a .22 mag. Not that I couldn't do it with a .223 - but then I would get away from a classic lever.
Let's face the reality ... we do it because we can. it's fun. There doesn't need to be a practical reason. I like a variety of cartridges to play with. I move from one to the other and back again. Who want's just one option?
That is one nice set of rifles William.
