>>A better analogy would be for you to make arrangements to rent a car on Orbitz, then find out the car rental company was nothing but a scam, and that they were renting stolen cars.<<
That model is utterly different from CL. It is actually 180 degrees different.
As I have said in other posts, the CL model is the bulleting board in a store or restaurant with business cards and ads. And should be treated as such - by those posting ads and those answering ads.
Caveot emptor.
>>Apparently, you are saying that the operators of websites have no responsibility to ensure that what is posted on their sites is valid.<<
If their business model is like CL, then the answer is a resounding YES.
Doesn't matter. They're both making money off a website. . they both should be vetting what is posted on it.