It's primarily for corrosion resistance. Nickel is less susceptible to corrosion in inclement weather/harsh conditions. Remington UMC aside, notice it's mostly carry or hunting ammo that's nickel plated.
Oh, it looks nice too.
MSgt, USAF, Retired
NRA Life Member
The hardest thing to explain is the glaringly evident which everybody had decided not to see. - Ayn Rand