Yes, information does make people happy. And my point is that a message that says "this site is hosted at Heroku" gives absolutely zero information to the vast majority of internet users. Most people simply don't know what that phrase means. It's no different than if someone suggested a new feature that is only visible for Opera users. It's just a waste of time and effort to do something that caters to such a small sliver of the market.

Also, a Heroku-specific error page would give zero help to the problem you describe above. Anecdotal evidence in this thread suggests Heroku sometimes goes down briefly for small chunks of its users. So if you see the Heroku error, it could be for just you. Or it could be system-wide outage. It wouldn't even solve that problem!