Just went through my whole contact list and tried every cash tag. I know for sure one person who's a bitcoiner and their's returned. Nobody else tho. 

Thinking through the moral implications of what I just did...

i was thinking it might have been a kyc thing.. your suggestion makes more sense


itsrealfake

I wonder if it's just for users who've interacted with bitcoin in some way? Didn't work for the contacts I tired either but did for my own.