I believe everyone should learn how to cook. Oh sure, you can say, tons of fast food restaurants are around, why not make use of them? TV dinners, catering, other people that you can rely on (haha)...
Cooking is fun. It's a bit like writing, actually. You first have this notion of what to make. Then you try to find a recipe, but you might end up using any ingredients that you might have instead of buying them from a nearby shop. Then you gather the ingredients, process them, voila. Perhaps you will try to taste the food and add other ingredients if need be. Or you might ask others to taste them first, in order to improve the flavor.
Why should one learn to cook? To me, being able to cook is a sign of independence. If you can bathe and do the things you do in the bathroom all by yourself, why not learn to cook? You can depend on yourself to survive--to eat, at least.
You can also show your love through cooking. Don't have a decent idea for your pal's birthday? Bake her a cake. Your friend is sick? Bring her some homemade soup. Your nephew, doing well at school? Give him a jar of cookies. No need to exhaust yourself finding the perfect gifts for your loved ones!