Because it's sturdy, inexpensive and forgiving to work with.
Easy to clean with a swish in some warm soapy water, grosgrain is a great ribbon to choose if you are making hair bows for little girls.
It never bleeds so you can safely use multiple colors together in one project. This makes it perfect for cheer bows because we know they're gonna get rained on.
And that same property makes it great for bows for babies as well. Come on, you know that bow's gonna...