Why would anyone use a Sickle?

I'm wondering about the use of Sickle of Boooal. It only gives 2d4 damage, that seems very little to me. Usually you want a weapon with the highest damage possible, right? So why would anyone go for the sickle of booal and not for a longsword or a mace? The one scenario I can imagine is not having a proficiency in swords/higher damage weapons.

Do people just use it for the lower levels and then discard it?

EDIT:

I just want to add that I don't know shit about fuck when it comes to this game, I'm on my first run so no experience with monks, sussur sickles and I barely know half of the words you people use. But I'm glad my question sparked a sickle debate and now I know 2d4 is not so bad.