Why season the meat "liberally"?
When it comes to steaks, there is specific reason to use a lot of salt.  The Serious Eats food lab goes into pretty good detail about salting a steak.  It has to do with drawing out the moisture on the surface of the steak.  This helps create a nice sear and affects the way the steak cooks.

For other types of meat, I assume they are just telling everyone to season more.  The amount of salt used in a commercial kitchen is unreal.