Why do we not see more intellectual property lawsuits as a result of these recent applications of screen scraping?

I was looking at the Wikipedia entry for web scraping:

http://en.wikipedia.org/wiki/Web_scraping

Under the "Legal Issues" section it talks about the tort issue called "Trespass To Chattels" which covers a wide variety of computer trespass crimes, including web scraping but from what I can tell there are very few recent lawsuits with respect to web scraping. The big one was Ticketmaster vs Tickets.com but that was back in 2000:

http://www.tomwbell.com/NetLaw/Ch07/Ticketmaster.html

Sites like popurls, alltop, google news, aggregate data from other news sites. According to copyright law, this should be permissable as long as the quote is limited and not a complete republication. These sites seem to follow this guideline.

But are there other recent sites that do not, who you would expect to fall afoul of the law? How do they avoid litigation - by asking the originating site for permission to republish? By paying the content owners for the privilege to republish? Or has the commonness of the Web2.0ish way of regurgitating content made this a moot issue by now - to the point where most original content owners have given up on trying to control the ownership of their content through litigation?