The October before covid me and Mrs. Asciimov went on a cruse with Royal Caribbean. We got dropped off at the port, put our luggage in the loading area, and proceeded to walk inside, all without talking to anyone.
Not 30 seconds after walking into the Port Building, a RCL rep walked up and greeted me and the mrs by first name. Said please walk this way, I have you all checked in, you just need to go through the returning voyagers boarding line. (metal detector/contraband check)
To be honest it was both creepy to have them just know who I was, and kinda awesome to get to skip the regular check in step. I asked the lady how she knew who we were, she told us that between the cameras in the port and the photos we submitted during the cruise purchase they knew who we where, and the information pops up on their tablet when they are assigned the next customer.