I think they usually are seeded - see
here. It's really standard procedure. In fact, on a couple of websites/forums I follow which discuss rankings etc. everyone always assumed there would be seedings. The news agencies just make out as if a big announcement was made when really it was expected all along, and it would have been a major suprise if they wouldn't have seeded.
Anyway, I understand where you are coming from, but I don't usually have such qualms, I just like seeing the best teams/players at the world cup. Although I do think it'll be interesting to see the fallout if a country like Argentina fail to qualify!
It is fairly usual practice in other sports too. For example, in cricket tournaments (ODI WC, T20 WC), high ranked countries finishing second in the group kept their higher seed advantage even though they finished second.
Also, if you take your opinion all the way, why have any seeding anywhere at all, for example when drawing up the groups in the first place? Everyone deserves the same chance as everyone else.
What do you mean, by the way, that the draw is fixed anyway? Do you really think FIFA doctor the draw?
Concerning New Zealand, I don't think it's any different to normal, it's just you're noticing it because it affects a country you're following. Last time was just as bad - the lowest Asian team played the lowest North American team - T&T vs Bahrain.
They've just swapped round the playoffs to more geographically acceptable ties.
Basically, they can't give Oceania no place, they have to have a minimum of a playoff. The best thing would have been to combine Oceania with Asia completely, but that's impossible because of the distances involved.
