I think competative shooting calls for different scopes. Sighting on a target with an aiming point at long range is somewhat different than shooting at a target with no aiming point, like a deer! Something I do with my variable scopes is I hunt with them on the lowest power. Better field of view and faster getting on target. Longer shot where a higher power might help you have time to make the adjustment normally. On the 50yd or less shot you probably don't. Take your rifle to the range and handling off hand at 100yds on high power see how long it takes you to get on targer and how much you actually move around. Then try it on the lowest power and you'll be able to see what i'm talking about!
Yes, to some degree there is a difference between a hunting scope, and a competition scope.
But the differences in glass quality are getting smaller.
Also a lot more FFP scopes used for hunting these days, where you used to only see them at competitions or military.
Your analogy of setting a scope to high power and aquiring a target offhand doesn't hold water.
Yes, it's a true statement.
But not practicle, or widely done by someone that's tried it once.
The difference between 3 vs 4 power is negligible at close distance. Where the vast majority of people would have their scope set for close quarters, or while walking.
The extra high end power when you have time to set up, and longer distances is not to be overlooked.
Can you hit a deer at 600 yards with a 4 power scope?
Yes. Depending upon the shooter.
Being able to pick WHERE on the deer at 600 yards only comes with higher magnification.