Ok, I think they key takeaway isn't that Kanye's "credibility goes down the drain" but that you shouldn't get in giant arguments with celebrities if you're the head of a company, even if they are known to be hot heads. I dunno, coming up with a slightly humorous retort like that won't really mitigate damage from having Kanye West rip on your company..

"Celebrities be warned: when you butt heads with Zappos, your credibility goes down the drain."

It's Kayne West, he has zero credibility.