A man was left raging after a self-service checkout machine asked him to leave a tip. While tipping is expected in some parts of the world, the customer was understandably left feeling baffled after being asked by a kiosk. The man simply purchased a chicken caesar wrap and a bottle of water at an airport shop, when the machine asked whether he'd like to leave a 15, 18 or 20 per cent tip. It didn't take long for Reddit users to jump in on the action, with one candidly asking: "Tip who exactly?" Another wrote: "This is especially annoying given how overpriced everything is at the airport. Then they have the nerve to ask for a tip". Meanwhile, a third joked: "Sure, it looks bad at first. But what you don't realize is, that self-serve kiosk is a single father with 4 kids, living paycheck to paycheck. He needs those tips more than we'll ever know." Reddit - Dive into anything from mildlyinfuriating As most are aware, the US is especially keen on tipping with a bare minimum of 15 to 20 per cent. Simon Calder, The Independent's travel correspondent outlined the basics to ensure tourists don't fall into the trap of breaking US travel etiquette. He explained that everything from taxis to dining and hotel staff are to be tipped. Taxis "expect an absolute minimum of 15 per cent," while if travellers are staying at an accommodation with bellhops, they are expected to "pay-per-bag". It is said that around a decade ago, 15 per cent was considered adequate for a meal at a restaurant. Now, the minimum has risen to 18 per cent. How to join the indy100's free WhatsApp channel Sign up for our free Indy100 weekly newsletter Have your say in our news democracy. Click the upvote icon at the top of the page to help raise this article through the indy100 rankings.