in my experience
The folks I work with often write their own little screen scrapers when data isn't exposed to them in any other way. Is the horribly coded website that they are scraping obsolete? Anything but. But, don't get me wrong, I like code that validates against it's DTD, and I love standards (because I hate double coding) because it all becomes more reusable and portable as requirements inevitably change. But this doesn't make old crappy code obselete, it just makes it more expensive to work with, and that is what's important in the real world, MONEY/COST. Don't forget that.