I saw a guy filling up one of these machine.

Source: https://steemit.com/monthlyauthorchallenge/@ace108/monthly-author-challenge-04-23-tuesdayorange-refilling-oranges-or-by-ace108
I found it's not all $2 though. I saw some locations charging $3.
Near my place there is one of these and another interesting vending machine turned up opposite it recently: A salmon vending machine.

Source: https://steemit.com/monthlyauthorchallenge/@ace108/monthly-author-challenge-07-09-tuesdayorange-salmon-vending-machine-or-by-ace108
Don't know what's next but there's one selling coconut in Suntec City.