See my answer to mikeryan's post above for information on why that is not necessarily the case. An individual phone number is worthless as well, the collection is valuable. But case law says a phonebook isn't covered by copyright.
1) You are comparing physical media to a web service
2) You are confusing content with access to content
Since you mentioned Phonebook, let's take yellowpages.com This site has much of the same information that a phonebook does. I would argue that it would be illegal for company B to scrape yellowpages.com for this information in order to make money without express permission from yellowpages.com. However, if Company B found another way to access the same information (ex: scanning physical phonebooks or asking people to sign up to their site) then I'd say they're within the law.
Craigslist is 100% within their rights to control who accesses their service and how. If CL users want to register for Padmapper and post the same ads on both services then that's their prerogative.
>if Company B found another way to access the same information (ex: scanning physical phonebooks or asking people to sign up to their site) then I'd say they're within the law.
Company B has found another way. They are getting the data from Google's cache of the craigslist.
Padmapper is not touching Craigslist's servers at all.
