I agree with referral abuse. I know a friend who knew about byteball, and shared it to our community. It resulted to betrayal among his mates who he had shared with the said program.
The scheme was, my friend was the one who teaches the newbies how to use the program, but little did he know, he was already taken advantage by someone he knew. You already what I mean, so yeah. I could say it's a little toxic for friendship's.