Very interesting, but the point that Indiana Jones made in The Last Crusade is valid. The cups used at the Last Supper would almost certainly not have been fine artistry. Most likely it was standard pottery. Furthermore, unless one of the disciples nicked it, the Holy Grail would have been washed up and used for the second sitting.
If the NT is correct, the Last Supper took place in a room vorrowed from a relatively rich person - possibly a religious sympathiser.
The Passover utensils were - and still are - set aside specifically for that purpose and must have belonged to the house owner.
I agree that they would not have been elaborate, and had to have been plain, though. The only decoration at the table would have been the menorah.
All the pascal utensils would have been set aside, and not used for any non-religious feast, being retained as family heirlooms and, therefore, used after Jesus' time, presumably being dispersed or destroyed at the fall of Jerusalem.