First off, there is the philosophy that no round that strikes its intended target is wasted, and the way you get rounds on their intended target is practice.
Some folks want to be able to put rounds on target, at any range, and at speed with a magnum, if they can. Doing that takes continual practice for some time, usually, and keeping that skill requires some practice all the time.
Those folks tend to shoot a lot.
Another point to consider, what magnums, what guns, and what uses you put them to. IF all I had were small frame .357s, I certainly wouldn't shoot them much with magnum ammo.
An N frame S&W is, for me, great in .357 and too light for comfort in .44 Mag. Certainly eminently useable, but not comfortable with full magnum ammo.
I know this is the revolver forum so a little off topic, but I have several magnum semi autos, huge and almost unwieldly compared to revolvers in the same calibers, but much, much more comfortable to shoot for the amount of power delivered.
A good heavy gun makes shooting even .44 Mag a fun thing, not a beat you up , but I can do this kind of thing. A lot of us find the blast and the recoil to be fun, as long as it doesn't actually hurt...
Done right one thing a lot of shooting does (and especially a lot of shooting the same load) is give you a feel for the gun and where to aim, at below the level of conscious thought. I don't think that's ever a bad thing...