I dont know. 
I have always felt part of the fun about posting is replying having the conversations. 


It might be more valuable as SN grows. It won't be as important for the OP to reply when there are enough stackers to carry the conversation.

Undisciplined

I always thought it was strange, but some of his posts are pretty good. 
They rarely reply back though. 

Satosora

Early on the gains were really big, but they seem to have leveled out.

@Rsync25
2.4m stacked \ 433.6k spent \ 8684 posts \ 909 comments \ 32 referrals

I think he roughly breaks even, but it doesn't seem worth the effort when there's no engagement.