Search ALL Craigslist using Google - What's the problem?

A lot of talk has been made about real-time results to search all of Craigslist, like crazedlist. But what about Google sites like allofcraigs.com?

I have posted ads on Craigslist that have indexed by Google within 2 hours. There is a small benefit to the delay, as most spam ads are flagged before Google indexes them. Fact is, nobody is going to search all of Craigslist using crazedlist, or allofcraigs.com, to find important items they can find locally, that's what craigslist is for. Therefore, real-time results are not that advantageous over sites that use Google custom search.

Thoughts?