Denmark censors a lot more than just TPB, though it is probably the one website that causes most people to circumvent the censorship.
In Denmark it all started out with blocking child porn sites, then it was expanded to copyright infringement, then it was expanded to companies operating illegally (counterfeit goods stores, illegal gambling, alternative medicine stores) and most recently the government started blocking "terror propaganda" [1] - which means they have begun censoring political speech.
This is in spite of a constitution forbidding censorship, with the counterpoint being that since it's technically private companies doing the censorship, it doesn't violate the constitution. Even though ISPs will be taken to court if they don't censor sites [2]
Sorry, but I did not intend to compare or conflate the two cases. I wanted to give an answer to the parent poster why those countries might be listed on the above site.
