Really, what could go wrong here:
the system would tell a male customer in his early 20s to order a set meal of crispy chicken hamburger, roasted chicken wings and coke for lunch, while a female customer in her 50s would get a recommendation of porridge and soybean milk for breakfast.
This is probably the future whether we like it or not. Face and voice recognition is reaching a tipping point where documenting and influencing individuals without consent is trivial. Sure, this has long been a tactic of human merchants the difference now is that the efforts can be coordinated and compiled across multiple outlets.