Hierarchical comes in very handy if your reusing blocks of a schematic in other projects, you just append the piece as a hierarchical sheet, wire up the pins to your top level block and off you go.
Global can be hard to find at times, but there are things like local voltage rails where i am happy to just call them global, but i get cautious just bulk naming on global as in bigger projects it can be very easy to end up reusing the same name and not realising until your final board reviews.
It can also help make your top level schematic act like your project mud map, a hierarchical bus between 2 sub sheets for your LCD data, etc, the tools are there to be used as you see fit.