I use it to finish the raw edges of fabrics before washing.
It's also great to finish the raw edges of the pieces used in bags and purses. Or to finish off the seam edges. Makes for a nice, professional looking finish instead of all those raw edges.
I do use it sometimes to finish the edge of the quilt before putting the binding on.
I may not use it every single day, but I would rather have it than not have it.