The Snow Chief package is often picked by dealers with the primary reason being the anti-slip diff but with the extra goodies people often want one or two of.
220 Amp Alternator
Anti-Spin Differential
Instrument Panel Mounted Auxiliary Switches
Clearance Lamps
Transfer Skid Plate
Off Road tires (sort of)
You get some decent things for not a huge price. I want the aux switches as I might add extras lights, winch etc., and the after market switches generally are poo stuck on the dash somewhere or costing about what the Snow Chief package cost anyway. The 220 Amp alternator won't hurt with those things. You can see where each thing might be helpful if you ever intend to plow.
Anti-spin is a must for me as my 2013 did NOT have it and here in MT in the winter they do help irrespective of all their criticisms, like at the mailboxes with the polished ice trying to get up the hill. I feel the slip grab instead of just sitting there spinning, backing up, sliding sideways and finally getting traction. Who doesn't want their transfer case better protected? The tires? Well, I'll be getting better ones once these even hint at bad performance in the winter, but I am not coughing up 1K plus for tires until I have to. The lights I didn't care one way or the other, but the wife noticed them and liked them so... And she's a keeper as she likes aftermarket bumpers and a winch... I also bought the AMP Research running boards. I didn't tell her what they cost but they were a MUST on the 2500... She does like the lights at night...