Okay, I'm curious as to what the purpose is of a salt crust grill.

I've seen them used on Iron Chef, and I found some recipes for them on the
net. What I haven't seen is a description of why in the world anyone would
encase meat in salt before cooking it! What benefit does it bring that
can't be realized with something commonplace as a sealed aluminum cover over
the pan? Wouldn't it make the meat ubearably salty?