trig42:
The US butter at Pak n Save is whiter (and saltier) than NZ Grass fed butter, but it's still butter.
Some people, and butter is a staple, may care about the politics but can't afford to be fussy. I have seen that butter at $6.49 and every dollar counts.
I think I'd still buy the Pam's at $7.19, but luckily for me I can afford to make that choice (I actually stocked up on Costco butter a couple of weeks back at $12.99 for 4x226g (so, the US butter is actually better value than that too).
CostCo butter is likely either Westland or Open Country...
https://www.ruralnewsgroup.co.nz/rural-news/rural-general-news/open-country-opens-butter-plant
