Yes you can.
Yes you can you can go at the last minute and they all accommodate you
Yes they don't care just want your money
Yes there are same day ticket sales.
Yes
Yes you can they start boarding 1 hour before cruise time. If there is a special even you may not get on board if you don't have a reservation
They will applaud your arrival
No
I believe you can but i would still try to book ahead and also call them first.
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