[tarmac]

You're still technically logging in by providing the copied cookie. I don't see any difference here.

Or say the title should be changed to "How to scrape your data from your sites that require login"

[almost]

Agreed, this more of a "how to scrape data from sites you can log into". It's not even a very useful example at that.

For anyone who wants to scrape sites that require login I'd recomend Python with Twill. That lets you do the whole thing with ease.

[geoscripting]

Twill is an option indeed, but this way you don't miss out on the javascript. You can take advantage of all of your browser's features.

[almost]

But the article is suggesting just copying cookies from Firefox into a simple Java based scraper. That won't support Javascript either.

If you needed Javascript you could use one of the Firefox scripting bridges (Selenium or MozRepl).