There would have been many empty jugs available. Why use the water pots that were used for washing when there were empty wine jugs all around?
John 2:6
ESV - 6 Now there were six stone water jars there for the Jewish rites of purification, each holding twenty or thirty gallons.
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Would the miracle have been more exciting if Jesus had used the discarded "wine jugs"? I don't see the reason it matters what He used to turn water to wine. It was His miracle, so He gets to choose what to use to put water in.
Also, if He had used the wine jugs someone might have said the jugs ALREADY HAD WINE IN THEM. I think it was better to use water pots. I think He knew that there would be unbelievers until eternity added another day, so He didn't want to give them any room to make hay of their rumors and innuendos.
Many have tried to come up with something to cast doubt on the efficacy of His power, but in the end they all crash and burn. He is who the bible says He is. He did what it says He did. And He will return and erase all doubt.