Their business is in billions of dollars, I'm sure some of them reads BHW, but I do not think they care as much as some people here thinks. They have much much bigger problems than few blackhatters really, who even do not hurt their site much, just making few bucks. Most people will never have technical abilities to use BH stuff and will just buy their stupid ads so I do not think they see us as big problem. Well they of course do not like us also, so I'm sure they will repair that email thing for example, but if they saw us as real problem, it would have been repaired long time ago as well as many other holes which you can use to get traffic from them for free.
Their real problem is that they are losing young users, which spends less and less time on FB and use other platforms to communicate with each other.