My humble opinion. (and all the dearth of worth that likely carries) As has been bandied about killing doesn't need to have anything to do with "stopping". Ponder for a moment some short range weapon (phaser on stun type thing) that 100% reliably stunned/staggered any charging beastie for a good 5-10 seconds but had no actual lethality whatsoever. A hunter would have little use for such a thing but a PH might be extremely intrigued. The reason obviously is the difference in priorities. A hunting arm's primary purpose is to put game on the ground. A stopping arm's primary purpose is to try to keep game from putting you on (or even under) the ground.
Gleaning information from people far more experienced than myself when dealing with those who make a living amongst things large and bitey and/or stompy there is a strong correlation with larger calibers. I think of this as nothing more than a hedge. All else being equal* if carrying a bit more rifle improves your odds in a worst case scenario by only 5% why not take that given the stakes? You could spend a lifetime dodging tooth/claw/tusk/horn and never have use for a "stopper" at all or even if you did what you had with you at the time be sufficient in that instance. OTOH what if that small advantage was the difference between talking cartridges here vs with St Peter? Ruark said "Use enough gun." and I've seen no reason to interpret that to mean "Minimum is good enough.". I've always taken it to mean "Enough starts at plenty." and when lives, perhaps yours, are in play I'm a Ruarkian. Of course I firmly believe everyone should do as they see fit.
*It's a minor pet peeve of mine but I've never understood the "accuracy trumps everything" mantra in caliber discussions. Guaranteed accuracy is arguably less reliable than cartridge performance so when discussing one why does the criteria of the other have to come into play? If we were all Francisco Scaramanga that would be one thing but we're not. When discussing calibers it seems we should consider the accuracy issue as a given in the comparison and proceed from there.
An intelligent reply, and in my view the only sane one.
