That's actually kind of a misrepresentation.
Universal distributed Shaun of the Dead both internationally and domestically.
Hot Fuzz was ostensibly distributed by "rogue media"; however, at the time of distribution, Rogue Pictures was a subsidiary of Focus Features, which is a subsidiary of NBCUniversal. Thus, in an incredibly roundabout way, Hot Fuzz was distributed by Universal. Now, since then, Rogue Pictures was bought by Relativity Media, which went bankrupt and got sold to UltraV Holdings company. I got no clue whether or not they own the rights to use Hot Fuzz in HHN, but then, Rogue Media did distribute The Strangers before they got bought, so I'm assuming that Uni still owns the theme park rights.
World's End is the same story, only that was distributed domestically by Focus Features, which is, again, a subsidiary of NBCUniversal. Plus, a Cornettos Trilogy dvd set has been released by Universal, so there is reason to believe that it can come if fan demand is high enough.