The Section Application; statement doesn't have to be present if...
you're not using the Section Access; statement. Section Application; is the default at the start of your script, even in the hidden script.
the Section Access; statement appears near to the end of your script, and there are are no more regular statements after Section Access; In that case all statements appearing before the Seciton Access; statement are parked in an "implicit" Section Application; area because that's the default area at the start of your Load scirpt.
Section Application - being the default at script start - is usually omitted altogether from scripts without security.
Scripts that have only Section Access; won't do many useful things (if any at all) because your document will end up without a data model... But I can imagine that a document with just a series of buttons that pass control to other documents (document chaning) won't need a data model and will do just fine with only a Section Access; statement