Befriending women is sometimes useful for becoming attractive to other women. (Allow me to skip the obligatory part where friendship is good in itself, of course it is, but I want to make a different point.) For example, you can ask them to help you shop for clothes, relying on their superior visual taste. Most of my "nice" clothes that I use for clubbing etc. were purchased this way, and girls seem to love this activity. Also they can bring you to events where you can meet other women; help you get into clubs; offer emotional support when you need it; and so on. If you make it very clear that you're not pursuing this specific girl sexually, being friends with her can make quite a substantial instrumental benefit.

That said, of course I don't mean the kind of "friendship" that girls offer when they reject you. That's just a peculiar noise they make with their mouths in such situations, it doesn't mean anything.