Why Craigslist!? Why do you block multi-posts in different cities?

Why do you consider the same post in a different city 2000 miles away a duplicate post? It's not like someone in Nashville is going see the same post in Los Angeles. You don't offer a nationwide search so why block multiple city posts?  I like to sell things in multiple cities and you make me have to slightly modify my message so that your filter doesn't block the post. Please limit this blocking feature to single a geographic area like a major city or county.  Thank you.