You say "it was nothing like what I knew from Norway." Does that mean in Norway you can have one crappy town charging 20% municipal taxes next to another crappy town charging only 10% municipal taxes, and this will have no effect on which town people want to live in?
I am not too familiar with the exact dynamics of the game, but I would think that as your SimCity becomes more awesome, higher taxes can be levied because people want to live there for other reasons. Is this not the case? I hope these social economists weren't just arguing, "taxes are high in Oslo, and there is no shortage of people who want to live there!"