I have to say, I can't imagine that has any weight on anything.
Some people have no friends. Some people have no friends that play D3. And some people just don't want to play with people, like me. Before I started botting, I never had any of my D3 playing friends on my list. I like to play solo.
In the event of an account review, I imagine it will be the exorbitant amount of playtime in a short amount of time, the seeming lack of need for sleep/food/bathroom breaks, and running the same general run 4 times an hour, every hour, every day, that gets you.
I can't imagine if you've done act III champ farming for 24/7 for 2-3 months, that they'd unban you because your friends list had real people on it.