How is that really any better? You should assume that if an attack can get to your database, they can get to your web servers and take all of that as well. Such a scheme certainly wouldn't have saved Gawker.
There's no reason why compromising the database would allow attackers into the web server, unless you've configured SSH to allow signing in from arbitrary remote systems.
http://www.theregister.co.uk/2010/11/23/network_card_rootkit...
(Why yes, I _did_ have that problem weighing on my mind while I investigated several machines that had a weekends worth of exposure to the recent Exim remote root exploit...)
I think you give people way too much credit. Maybe config files aren't "typically" world-readable but they ARE typically httpd-readable.
It's a mistake to assume, that because you might follow best-practices, the rest of the people out there do. You said yourself in a comment on this same post that many people make mistakes because they're too lazy to take that "half an hour of research." Let's make the assumption that that is typical.
> There's no reason why compromising the database would allow attackers into the web server, unless you've configured SSH to allow signing in from arbitrary remote systems.
Oh, you mean the default behavior? See above.
The point is, if someone has gotten enough access that they can actually get a raw copy of the database, it's just as likely they can get a raw copy of the config files, or /etc/shadow, or whatever else is on the host system.