With a team of 45 people aged between 18-25, he said it was important for young people to vote, especially after the year the country has been through with the Covid-19 pandemic.
Joyce said the flavours and scoop poll had created opportunities and "encouraged young people to vote and have conversation around voting".
On its launch day, the Electoral Commission set up a stand, and enrolment forms can be found at the shop.
Each day a "scoop poll" is created, where customers and staff can see which was the most popular flavour of the day.
A whole hour of free scoops of "Jacinda Fever" was then given away because of her visit.
Joyce encouraged any other politicians to visit the store so customers can get a free scoop which will boost their chances on the "scoop poll".
Joyce told the Herald customers were really enjoying the flavours and their concepts - and some were even creating a "double scoop coalition" - pairing two flavours.
He told the Herald he and his staff were "having a lot of fun with it".
"We'll pack ya a phat cone. Mixing it up with 'The Bro's Green'."
• "Naughty Ol' Winston" - for New Zealand First Leader Winston Peters made with liquorice and chocolate lumps.
"Stirrin the media & schmmoshin our Grans with creamy liquorice gelato & chocolate lumps. Forget the polls ladies, put your feet up & lick this baby!"
• "Cookie Crusher Collins" - National Party Leader Judith Collins has a cookies and cream-inspired flavour.
"Brave, brave Judy threw down her gauntlet. Will she whip her arch-enemy with the creamiest organic milk gelato, crushin choccy cookies & an extra strong cookie cream economy?"