"As a NZer who has no business here. The f*** is this s***? Even our Sunday vege market stalls at the local schools have eftpos," the user wrote.
Another user responded with a picture of a China Bar restaurant sign, that announced a similar A$30 minimum transaction amount.
It is unclear where the two photos were taken. Daily Mail Australia has reached out to the uploaders for comment.
As some Reddit users pointed out, some Australian banks restrict merchants from imposing minimum EFTPOS amounts.
Commonwealth Bank writes in its merchant agreement rules that businesses "must not impose any minimum transaction amount for card transactions."
National Australia Bank has a similar stipulation in its merchant agreement, while ANZ, Westpac and St George banks don't appear to regulate minimum amounts.