After seeing the photo - a Getty Image stock shot taken during a photo shoot last year - Freeman messaged Ardern on social media asking why her Government had chosen to use her face to promote the Budget.
Ardern has now responded to her question.
In a reply today on Instagram, Ardern said the Budget was all about "happiness".
"Simple reason really - happiness. You both looked really happy."
Freeman replied cheekily from the Gold Coast: "We are."
Freeman, model and actor, said the high cost of living in Auckland was a major factor in her decision to move overseas.
"We moved to Auckland to do the TV thing but I couldn't pay the rent ... sometimes I would have to hire a sitter to look after my girl while I went and did some TV work and I was paying the sitter more than I was coming home with because I was passionate.
"I didn't do it a lot because it made me feel kinda stupid, paying a 15-year-old sitter more than what a single mum is making. It was crazy."
Freeman said she was paying $500 a week in rent but was short about $200 each week - and she still had to feed them both.
"I just said to my daughter I can't do another year here ... the TV stuff was going well, it was good but not great pay, when you're just an extra or featured. It was hard and my daughter was like 'yeah Mum, just tell me when and I'll pack my bags'.
"She didn't really enjoy school in Auckland either, she had a grumpy teacher."
The pair left for Australia in December.
As for politics, Freeman said she wasn't political at all - and said if she had to choose she'd vote for the Greens.
"I don't follow [politics] at all, to be honest. I would vote Greens because I'm a bit of gypsy and I don't get into what's going on. I just choose to tune out because I'm one person and if I get really passionate and upset about it what's that actually doing for my soul and wellbeing?
"It doesn't help me, it doesn't help the world, I just choose to be really passive and whatever they're going to do, they're going to do."
