The CFAA makes it unlawful to exceed authorized access to any protected computer system (essentially, any computer in the United States). If someone claims that you've violated their ToS, they almost always also claim that by so doing, you've also violated the CFAA, since your access "exceeded authorization" as granted within the ToS, which they'll claim you've agreed to.
Now your breach of contract is upgraded to a federal crime. Better hope you don't make the wrong MegaCorp mad.
Disclaimer: I'm not a lawyer.
“Zillow has a legal obligation to honor the agreements we make with our listing providers about how photos can be used,” Zillow tells The Verge in a statement. “We are asking this blogger to take down the photos that are protected by copyright rules, but we did not demand she shut down her blog and hope she can find a way to continue her work.”
The public face of Zillow says they hope she can find a way to continue her work, yet the corporate counsel pulls out a piece of legislation that could see her spending the rest of her twenties in a jail cell. That's dirty pool...
Point in your favour though, the Verge didn't even mention the CFAA in their coverage of this. So, I would agree that it's common, but just because something is common doesn't make it right.
It is probably less likely that Zillow is intentionally trying to play hardball, and more likely that they pulled out the "Terms of Use violation" boilerplate and made the necessary adjustments.
People are successfully sued under the civil provisions of the CFAA on a regular basis and they rarely have to face the possibility of spending their twenties in a jail cell for conventional scraping or copyright infringement (another thing that has both criminal and civil penalties).
weev is an exception presumably because his disclosure contained a bunch of personally identifiable information from Very Important People. Swartz was an exception probably because he was apprehended by police for illegally breaking and entering a network closet at MIT, triggering the prosecutor's question "What crimes did this guy commit to justify his arrest?".
The CFAA is terrible law, and I say that on HN so much that it will probably be the next thing dang yells at me for saying too much. Large companies like Zillow abuse the legal system to strongarm small entrepreneurs and publishers, and that's disgusting. The fact that it's possible shows that, in large measure, we've lost the plot.
We need serious reform not just for the CFAA, but the legal processes that allow this state of affairs.
weev was convicted and sent to prison for violating the CFAA, based on his "unauthorized access" to AT&T's site (the limits of which are presumably defined by the ToS). His conviction was reversed on the technicality of improper venue, not the dubious nature of the conviction or the belief that ToS should not be eval'd into federal law.