Crocheting is one of those hobbies that, if pressed, you could call "practical". You could also call it an obsession, a way to make a living, and something to aid in dieting - after all, if both hands are occupied with hook and yarn, they can't put food in your mouth.
The ability to make clothes, blankets, toys, decorations and other items out of yarn is also a very simple way to help others. Many charities will accept, or have been formed to make and distribute the former three things listed to the homeless, ill, or victims of natural disasters.
Crocheters can be "yarnies" or "threadies", depending on preference, and contract "diseases" such as Yarn Acquistion Syndrome, Pattern Acquistion Syndrome, and Hook Acquistion Syndrome.
Crocheting is a harmless obsession - except to one's wallet and bank account.