[jaredsohn]

The problem is that if another site has the same listings as Craigslist and provides a better user experience, people looking to rent an apartment will start visiting that site instead of Craigslist. Over time, people looking to list apartments that want an audience of renters would start listing on that site directly instead of Craigslist, since that is now the best place to find renters.

[creativename]

Ah, so in that case it would literally come down to not wanting to have to innovate. If they truly thought that people preferred to have it the way it is, you'd think that they wouldn't be afraid of this.