It hits with a higher velocity allowing it to penetrate the target food. Fancy restaurants will use a step ladder and pop out a couple ceiling tiles to get that extra height. They say after 12 ft you can't taste it but they just have uncultured palates

But you don't have to look like a complete prat when doing so. That's a choice.

Also, just dumping salt from high up give you a slightly larger dusting in one spot. If you're trying to spread it evenly, you only need to go like 3-4 inches up and move your hand around as you sprinkle. lol.