I thought the same thing! The way he kept drinking that water, jerking his head back and forth, twitching in the chair. Totally uncomfortable.
On another forum, someone had a theory that Brooks is blackmailing Vicki. Lots of speculation that Vicki and Brooks were involved WELL before Vicki and Don were ever divorced, and if Brooks has proof of this and exposes it, it's possible Don could be entitled to even more of Vicki's money. Also, those "miracle juices" Vicki and Brooks were promoting during the show, someone thought maybe Brooks was blackmailing Vicki saying he'd expose the fraud of that which would ultimately affect her insurance business.
Frankly, I don't know how Vicki's insurance business hasn't taken a hit as a result of the show. I think it initially grew quite a bit as a result of Vicki's notoriety, but I probably wouldn't give my business to someone as emotionally unstable and scatterbrained as Vicki. How could I trust her to underwrite my life insurance when she can't even see the writing on the wall about Brooks?