Night 'n Day general manager Matthew Lane described the level of thefts as rampant.
"It always seems to be this time of year in particular.
"You get new students in town. It's quite a common denominator."
Stores had security staff, and people were monitoring store security cameras.
"It's frustrating to say the least.
"It is one where people tend to lose their social conscience a bit when they've been drinking.
"Would these people come in at 9am on their way to work and pinch a pie? No, they wouldn't.
"I don't think there is an understanding of the impact it does have on local businesses."
At 10.35pm on Wednesday, a 49-year-old man tried to steal $13 worth of items from the Regent Rd store by putting them in his jacket and walking out, Senior Sergeant Craig Dinnissen said.
Half an hour later, a 20-year-old man was seen putting two pies in one pie bag, and then eating one of the pies while in line waiting to pay.
He made no attempt to pay for the pie he ate.
Twenty minutes later, pies were targeted again, this time by a 21-year-old man who put a pie down his pants and tried to walk out of the store.
And at 12.50am, an 18-year-old man was spotted putting a pack of cards in his jacket pocket before going to the counter to pay for other items.
All were stopped by security and trespassed.