Sifting or not has nothing to do with a course texture. While sifting will give you a lighter and softer texture, not sifting does not guarantee a course texture. Not sifting, measuring straight out of the bag, "scoop and level method" gains you nothing, and in fact is basically being lazy by the person who developed the recipe but who thinks, incorrectly, that they are being consistent. The problem is the amount of settling of the flour in the bag or bin is an unknown factor and can make the measure vary from scoop to scoop giving the recipe uneven results. Sifting gives you a uniform measure of volume and is the second best method. The best method for baking is to measure by weight. Measuring by weight will always produce a uniform product.
Some people who develop a recipe they care to share lack certain skills used in baking, such as always using sifted flour, and may not even own a sifter.
Another reason for sifting, although not typically a problem these days, is to sift out broken pieces of machinery that may have made their way into the flour.
But one reason I still prefer to sift, is to remove "flour bugs", hair, rodent feces and other non-flour material. I still find enough to make it worth my while in screening the flour to keep "junk" out of my bread.
"Food is our common ground, a universal experience." - James Beard