Even when the price of a possum skin reached the equivalent of $20, the human catch rate of possums (about 2 million skins a year) still represented about 10% of the natural breeding rate (about 20 million+) and those that were caught tended to be from the easily accessible areas.
I live in a very remote part of NZ and there simply aren't people here who want to head off into the incredibly rugged bush to get possum skins. Nor, I suspect, despite great marketing are there a huge pool of people who can afford to pay $300+ for a possum fur sweater or associated productin these recessionary times. Have you seen the price of some of these possums fur products?
The other problem that arises is the people who are catching possums then start campaigning against possum control operations by DOC that are being run to save birds and rare plants in the special conservation areas. Snowy Peaks/Untouched World's owner is one of these anti 1080 pest control advocates. There is abundant science showing that ground methods simply are insufficient to get pest numbers low enough in these areas to enable the native biodiversity to survive and prosper.
My conclusion is that harvesting possums for fur (or even pet food) will make a contribution, but to save our special plants and animals we also have to continue with extensive conservation funded pest control operations. It is important to keep encouraging the people who are doing pest control including harvesting possums but it isn't the complete answer.
Remember also that possums are only part of the problem. One of the best dimensions to the pest control operations using 1080 is that this method also control rats and stoats that are not targetted by possum harvesters. Stoats kill 95% of the kiwi chicks. Rats have a devastating impact on most native birds. In Tongariro Forest an extensive 1080 operation two years ago resulted in a major surge in kiwi breeding success.