Spark press release makes a point of pointing out the competitors are really "not New Zealand companies":
“More and more New Zealanders have been choosing Spark in the last few years, and their trust in us reinforces our commitment to New Zealand. Should this proposal clear the hurdles in its way, it would mean that Spark remains the only major industry player controlled from New Zealand, with 2 Degrees controlled out of the US, Vocus out of Australia and Sky TV/Vodafone NZ out of the UK.”
We are in a global market place so being offshore controlled is not a negative. This PR gives me the feeling that Spark are nervous.