"It's definitely brought people in on the quieter nights," Jansen said.
"I also find even on busier evenings you'll have people come in the earlier part of the evening because if it works out, sweet you can go to dinner and if not, oh well you haven't lost your evening."
While she would never ask someone if they were there on a Tinder date, it was usually obvious, Jansen said.
"Tinders will always sit on the opposite side of the table from each other while established couples will sit next to each other.
"On Friday night we had three Tinder dates all beautifully lined up in a row, it was like a gallery of Tinders."
People on first dates made for nice customers, she said, they were "on their best behaviour" and trying to make a good impression.
Underground watering hole the Jefferson in Auckland's CBD also saw a "noticeable" number of people in during the week on Tinder dates.
"They stand out like a sore thumb," said owner Osir Yudilevich.
"It's just the awkwardness - the physical distance at first. It's their first physical face-to-face interaction, taking it from the app to the real world. The first few minutes can be a bit stand-offish."
The Jefferson had been open for only about a year - but in that time, Yudilevich said, he had seen the number of Tinder dates at his bar increase.
"You see it more and more - at least once a day I see it, especially on quieter days, midweek."
It was the same story in other suburbs, with bars in Herne Bay and Ponsonby saying Tinder dates kept business ticking over on quiet nights.
Ella Pawson, bar manager at Mr Tom's on Ponsonby Rd, said as many as 20 per cent of midweek customers were in on dates.
"During the quieter nights you definitely notice it more," she said.
"We've got one lady who goes on six different dates a week and she always comes here."
At the ever-popular Golden Dawn, manager Nick Harrison said anything getting people through the door was good news for business and there had been a noticeable increase in Tinder dates in the past two years.
"With Netflix and everything people aren't seeming to go out as much. On Tuesday and Wednesday they [Tinder daters] do come out quite a bit."
He said the telltale signs were anxious or excited looking couples who were perhaps drinking a little faster than other customers.
"People can get married and have babies in six years' time and you saw it all start on a Tinder date."