Lucky you for getting the Royal treatment. I was on a flight (EI not RYR) from Gatwick to Shannon in June last year and was the sole passenger. The crew closed the doors and as I was seated in ~ row 14 I got up prior to push back and asked could I sit in row 1 since there was nobody else on board. Unfortunately I was promptly advised for "safety" reasons that I must stay in my allocated seat for takeoff and landing. Not wantpmg to antagonise the crew member and risk an unwarranted delay to the flight etc I dare not mention why the reason for the "safety" i.e. is it in the event of a crash so they could identify the body. In my own head I was thinking, shur if we do crash, there are ~6 crew and one passenger so not hard to identify.
The thing that got me was that I never saw a crew member for the whole flight and used my call bell to summon them (fasten seat belt sign remained on for the whole flight) to try and pay for a cup of coffee & a full Irish.