Notice that e.g. on the coffee example I specifically didn't suggest ordering coffee automatically for you or something. I buy fresh grinded(is that the right word?) coffee myself that I buy from a local coffee shop so all I would want is a reminder-maybe a specific text file where I input the stuff that I need to buy and the coffee machine adds coffee on it automatically. Then I can sync that file to my phone when I go shopping( maybe a couple of QR codes?).
Anyway the point of home IOT for me would be to get ease the mental load of keeping up with the house and maybe save some time with e.g. the bath tub( maybe if you decide to connect the system to your smartphone with e.g. a key exchange via lan you could tell the bath tub to extend the time that it keeps the water ready).