This projection isn't been used, right?

Correct: it's here as a reference for the case where you want to plot lon, lat data (as dots) on the map.

Makes sense... however, I spent a while searching for where was the projection been used on the example... Wouldn't it be better to remove it? or maybe add a comment explaining why it is there

there's a comment in the paragraph just above :) "To overlay data on the map…"

Totally missed that. Thanks!