This explains Sainsbury’s recent scramble to open the first till-free store in the UK, a PR coup ahead of Amazon’s inevitable incursion.

And they’re not alone – pretty much every grocer from Tesco to Marks & Spencer is trialling scan-and-go technology, self-ordering kiosks are now the norm at McDonald’s and, meanwhile, Argos quietly launched its first self-service digital store last month. Time is the new currency.

Checkout-free shopping will particularly cater to busy city workers on their lunch break and it will undoubtedly hit travel retail hard – till-free will become the norm in airports and train stations five years from now. But is this really the future of retail?