How would I use proto-types of proto-types in the workplace?

Hey everyone,

I am just completed this exercise:

However, I’m struggling to see a real world use for accessing the prototypes of my of my Object’s prototypes. In the exercise we test to see if the protoype of all objects is also a protoype of Dog.prototype. Could someone give me an example of how one might use this functionality in building website or online application? I’m sure it exists, I just have a hard time seeing it.