נֶגֶד neged "before, in front of" the use in Amos 4:3 is neatly opposite of that in the story of Joshua at Jericho. There the Israelites enter the city "each man straight ahead" through the many breaches in the fallen walls. Here the oppressive women of Samaria (Israel's capital) leave the city "each woman straight ahead" through the many breaches!

In Am 9:3 its use reinforces the stupidity of trying to hide from one's creator. (They may be "away" from in front of his eyes, but not hidden!)