Comment by snarf21

Because Facebook wants to run Snap into the ground. That is why they are trying to steal all of their users to their own messaging apps. Instagram Stories has done that some but they want more. There are also some users that would prefer to just use one app than have 5 to switch between. The carrot is 'You already use WhatsApp and now you can do Snapchat without leaving. Cool, huh?' I'm not sure I agree but I think that is the attack vector.