So about buying rocks for tumbling online

I got a paper yesterday from the post office that a box arrived, and I knew it's some rocks for tumbling from an Ebay seller. Based on the value given, I knew I should be paying taxes on it :-/

So hubby goes today to the PO to pick up my parcel and then he calls me. I ask how much did he pay, and he said 'nothing'. I ask 'how come'. Well, he says, when they asked what's in the box, he said it's rocks. They like 'what?? :o'. To cut a long story short, they were going back and forth with hubby as they didn't believe him, as in 'say again, what's in the box'?? Then they said they will open the box to check, so hubby said to 'go ahead'. When they opened the box and saw that there WERE rocks in it (and some grit, ok), they were on the floor laughing. ::) Hubby tried to maintain what dignity he could, and he left from there graciously after they told him he doesn't need to pay for the package...