Fashion boutiques and food retailers were among the stores open what is traditionally one of the few quiet days for the retail sector.

Fashion boutique owner Tace Constantine has opened on Good Friday for the past three years, because it always proves to be a busy day.

"Generally people are walking around looking for something to do," Ms Constantine said.

She said one of her customers arrived after visiting Acland Street in St Kilda, which was unexpectedly quiet for a public holiday.

She disagreed that it was financially unviable to open on public holidays: "I'm the owner so I'm happy to work it, and it's actually been quite a busy sales day."

Cazzandra Bell, from children's store Little Urban, said that opening on Good Friday was more about exposure than financial gain.

"The people who come in on days like today have an opportunity to really look at our stock, rather than quickly passing through during the week," Ms Bell said.

"Today is great for exposure and gaining potential new customers."

Cafes, such as Seven:am, applied a 10 per cent public holiday surcharge. Worker Adele Drury said that customers relied on them to be open.

She agreed with Ms Bell's assessment that Good Friday was an opportunity to increase exposure and gain new customers.

Fish shop Hunky Dory manager Beck Clinnick said the store was taking the opportunity to fundraise for the Good Friday Appeal.

She said the large number of customers meant she needed to put on extra staff, which was a financial constraint.

"It's been a steady day for us," she said.