Yep, even for shared accounts... only one registered person, the app only on one device, phone number has to be registered with the account owner. If you want to change your phone or tablet or whatever you use, you need to go to the bank. That's how it is, at least for Bangkok Bank.
It works pretty well at Phuket, and you just need your passport... nothing else. And... there are much more expats at Phuket than in Chonburi or Chiang Mai.
Yes, you are right. But you can print it out, take to your bank and they'll stamp it. And with that the Immigration is happy. Talking from my own experience...