The person who made a referral bonus off of me when I got hired had never met me in person before I got hired, but has grown to be my closest friend here. When they asked me in my interview how I had met so and so, I told them the truth and they were like, "oh, ok."
The one referral bonus I've gotten thus far was from someone who I had never met before he got hired.
They really don't care. Someone in management once commented that the highest number of referrals one person had earned is 7, mostly from online.