LayerMask.GetMask() vs bit-shifting

I've seen multiple tutorials that told me to use bit-shifting to create a LayerMask, like this:

Code (CSharp):

1. int layerMask = 1 << LayerMask.NameToLayer("Test");

But I just noticed there's this function called GetMask() that does the exact same thing:

Code (CSharp):

1. LayerMask lm = LayerMask.GetMask("Test");

What's the difference? Why use bit-shifting (which honestly feels completely out of place in Unity) when there's this function that does it for me?