You shouldn't use a naked domain anyways, you'll never be able to grow a site on a naked domain properly for various reasons.
https://devcenter.heroku.com/articles/apex-domains http://www.hyperarts.com/blog/www-vs-non-www-for-your-canoni...
No doubt there's ways around any problem with a naked domain, but why work so hard on something so trivial? No user has ever turned away from a website because it hadd "www." in front. That said, your naked domain surely needs to redirect to your "www." address if you set it up this way.
As for why, well, personally I prefer the look of a domain without the "www". It looks cleaner to me.
Let's agree that for the most part it's a bad idea to change from www to naked or the other way around after the launch of a website (for seo reasons). So you have to pick one at launch and try to stick with it. Why choose the option that looks nicer but has problems associated with it and potential vendors not supporting it, vs the one that arguably looks messy but that all users everywhere are well accustomed to and has none of the configuration issues that affect naked domains?
There's postmortems out there about using naked domains and DDoS attacks. There's issues with load balancing, with domain configuration, with cookies.
If your website gets overrun by HNers, what's your plan to compensate quickly? How much of your plan is bogged down by the fact that you're on a naked domain?