Uber drivers main income does not come from referrals and they don't need to rely on referrals because driving makes them enough money.
It's has become pretty obvious that genesis mining users need to constantly be upgrading to make significant returns because of the increasing mining difficulty so they are everywhere on the internet promoting their codes.
Even Craig Grant recently said in one of his videos "If it wasn't for me getting referrals, I wouldn't be in genesis mining upgrading" also this "If you aren't getting referrals then you have something to complain about" -because of the lack of significant returns. I can post the video if you want.