You are correct--nobody wishes to deny the other services the privilige of the service duties for Marines--go ahead and wait the tables, carry the bags, etc.
Fitting!
Then, I guess you're completely unfamiliar with the M109 SP Howitzer or the M3 Bradley CFV? Facts is facts.
BTW, that airfield that was "seized"? That was already occupied by US Army soldiers. I guess we'll have to revisit the term "seized", too?