Dust or Oil on D600 is this acceptable?

Camera 1 week old and taken about 100 images, 24-120 been on since new and never removed.

I have tried a Giottos blower to remove the dust and done it 3 times and still cant remove the dust, so I am assuming its oil?

I am thinking of sending this back to Amazon for an exchange, BUT, I guess I could just get another one with even more oil on it?

To be honest I don't see why I should have to pay £75 for a sensor clean or even have to pay postage to send it back to Nikon.

Am I expecting too much?

Is this amount of oil/dust excessive on a new camera?

Ok I admit this is at f16 but its still there right the way down to f8 and then its almost gone but if you adjust levels its still there!