Exactly, the point is Facebook at anytime can change the client to show ads, or send some of the text up for analysis. The point being the user is not in control. It's all based on trust. Do you trust Facebook won't do it? Do you trust Facebook won't be hacked and does it, etc.. some of the senators attempted to highlight that. One guy asked if Zuckerberg could few is stuff, and Zuckerberg had to admit that technically he could.