Animania Animal Rescue & Pet Shop owner Michelle Sigley said the store had been busy over December and was now "flat out".
"Even the suppliers are saying it's absolutely mad now, and they don't know why, because normally it drops at this time of year.
"It seems to be way more steady this year. Everyone's just spending, they were spending up until Christmas and they kept spending, there was no real peak and real drop off.
"It's just flat out busy."
Fish and aquarium accessories had proved popular, as had puppies and rabbits.
"Some years everyone wants puppies and the next year everyone wants bunnies."
Ms Sigley said she expected the rush to continue through until the winter months, although trade was weather-dependent.
"No one's going to buy a puppy when it's pouring down with rain."
Nationally, spending in December was up for the third month in a row, but did not post a significant jump. Paymark's seasonally adjusted total spend rose 0.5 per cent from November to December.
The festive spirit was evident in a 7.1 per cent spending surge at cafes and restaurants, an 8 per cent jump at liquor retailers and a 6.3 per cent rise at department stores.
NZ Retailers Association chief executive John Albertson said last month was in line with retailers' expectations.
"Obviously, retailers get reasonably optimistic ... you think that maybe this year will be better than expectations."
While retailers had passed the annual peak, the end of January brought with it summer season sales for clothing retailers and back-to-school trade.
"So there's still quite a few things that people can lock promotions around and generate a bit of excitement around."
Mr Albertson said while retailers were not predicting 2013 to be an easy year, there were signs the market was improving.
Paymark spokesman Paul Whiston said that, despite the pre-Christmas splurge, the December spending increase remained below average, at 2.3 per cent year-on-year.
However, when adjusted for seasonal fluctuations it was a more positive 4.3 per cent.
"These annual growth rates remain below those recorded before 2008, which is indicative of the slower economic growth since the global financial crisis.
"The fact that there were five Sundays and Mondays during December - typically slower days of the week - compared with only four in 2011 affects the raw year-on-year comparison and sometimes doesn't tell the full story."
While it was still tough going for some retailers, the seasonally adjusted numbers reflected an encouraging finish to 2012 - which included a 13.4 per cent lift on Boxing Day sales for retailers.
The average transaction value was $49.92. APNZ