I think only the users reading translations are the ones really discussing the finer points of Palahniuk. I'm not asserting any sort of regional supremacy, I'm just speculating that, as an American reading the books in their native language, that the Finnish translations are probably lacking the almost kitschy sort of transgression seemingly for transgression's sake and the clumsy rebellious sort of tropes that I feel attracts him to an American audience who are too scared to have anything deeper than a cursory interest in transgression but who maybe pride themselves on being "edgy" considering their interest in Palahniuk and those and that tangentially similar. Everyone I know personally who likes this guy is unbearable and I try hard to stay away from them because they all fit into this milieu of similar characteristics and tendencies that I cannot relate to and do not care to be familiar and/or friendly toward.
I know absolutely nothing of the Finnish language. So, whereas I know just enough of the translation process from an original Russian work- prose whose native articulation is overripened with feeling and passion- being condensed into English, a language that, by comparison, is cold, mechanical and utilitarian, and just knowing generally that not only is a lot of cultural significance lost through translation but even that the author's vision often becomes obedient to the whim of the translator, I'm going to go ahead and say that it's possible Finnish translations of Palahniuk's works are presenting his themes and tropes and so on in a much different light than they are presented in in the native English.