I still get occasional battle net whispers asking why the hell I'm now a battle net friend (I'm running the newest version). It needs to be in a very obvious pop-up, maybe when you log in, as a one time or every log in reminder, apparently, that having the oqueue addon installed and active means you will have random strangers as battle.net friends. People install this addon and don't realize it's going to populate their friends list. This typically happens soon after clicking find mesh.

If they can't be bothered to read FAQs and Battle.net notes, I'm not sure a pop-up will help. Just kick them off your list like I do since they are quite easily replaced.