One, I really don't. And two, you're the one making a positive claim that it's not addictive. If you don't want to back your claims, I can certainly live with ignoring them.
One, you really do need to show Facebook is addictive since you're the one arguing that it needs to be "corrected" from what it is now.
Two, I'm not making a positive claim that it's not addictive. I'm saying that it's not inherently addictive like an addictive substance that physiologically changes your brain and neurochemical pathways (i.e., nicotine). I fully accept that Facebook is addictive in the same way as video games, exercise, food, or sex, in that it generates a dopamine response.