so in theory they might send it back, but every single news article about this indicates that they get destroyed, so that seems to be the “in practice” reality.

I’ve only had stuff seized in Australia but when you think about how many thousands of people transit through each customs checkpoint daily (and how many people just bring stuff without really thinking about it at all) it would be a huge logistical challenge to track and return things. As I understand it, at the time I could have taken a receipt and paid a lot to try and get the things released but they were blatantly illegal so I was never keeping them. For the most part everything that isn’t significant enough to result in fines or criminal charges just goes in a big bin off to the incinerators.

I suppose it would also be just ethically/morally/legally inconsistent for the government to ban something but also facilitate its distribution as you depart. So yea I doubt this happens in practice except at large commercial scale.