A waiter recording your order is at a completely different, much smaller scale. Additionally, the waiter is an anonymizing wall between the system that records my order and me and will only correlate orders across multiple visits to the same restaurant. Not potentially across single visits to multiple, geographically highly separated, restaurants.
Look, all these micro-arguments about the micro-invasions of privacy are 'bread and circuses' [0]. We've entirely lost sight of what it means to be a private citizen just going about our own lives without every nanosecond being tracked, without every damn interaction being an opportunity for someone to skim a cent. Any micro-invasion can be 'justified': it's more convenient, I don't care about a restaurant chain knowing what I've ordered, I don't want to talk to other people, etc. But they all add up.
Societies are increasingly unhappy, anxious, overweight, polarised. The gap between ultra-rich and regular citizens is widening. It all adds up.
Yeah.. old man, cloud. Whatever. The overall evidence is stark and obvious, it just hides in the tiny details.
It's easier to choose from an online system because it's up to date with what's in stock
Why has privacy become something that is only available to a dwindling few? What price convenience?
No one cares if the worst thing that happens is they get slightly better ads
As for the arguments that QR codes are somehow a time-saver, they can be a real time waster. Find phone (not glued to my eyeballs), scan QR, swerve option to install app, wait for enormously bloated website to render badly, get frustrated trying to find what I want, get up to find a staff member to order something but with X instead of Y please if that's possible, can I pay with cash, etc etc etc.
Clearly, everyone's needs and experiences are different. If you like QR codes in cafes, fine, but we should recognise that they represent something other than supposed 'convenience'. They are there to gather data, and to allow cafes to hire fewer staff. They represent the creeping invasion of privacy in every possible aspect of life. The fact that cafes may want to hire fewer staff masks the issue that an increasing number need to in order to survive. Small business margins are squeezed by unreasonable costs and shrinking profit margins, and these pressures are instinctively passed down to the customer -- you and me. Rather than mindlessly capitulate to this and encourage the one-way downward spiral, I really would hope for communities such as HN to see opportunities to 'disrupt upwards'. How can businesses resist exorbitant rents? Why are our lives so hectic that talking to a waiter is seen as too slow? Why do we give away data without being an eyelid?