The thing that I don't understand is why returning them would impose a large import tax, when it was simply going back to country of origin and manufacture. How does that make any sense? And would that import tax on a mere 2000 devices really have exceeded the cost of destroying them?
Returning them is also more sound because at least then you can re-skin them and sell them eventually.
To me if you are going to manufacture anything it only makes sense that you would ensure the ability to return the products in case of an issue. What if they had simply delivered devices that didn't work? It seems like the same import tax dilemma would have applied.
If they had defective units, those would probably have been trashed and replaced, too. The numbers just don't work for them to do anything besides trash them.
Playing fast and loose with the numbers we're given, here's what it seems like to me: There are 2000 meters in question, which they retail for $15 each, which is where the $30k comes from. Let's say they purchased them at $5 each from the manufacturer, which is probably on the high side given the margins that Sparkfun would need to make this a profitable venture. The manufacturer could not have spent more than $3 each for them to make a profit. We know from their post that Sparkfun has been given 30 days by customs to sort this out, and they are facing a $150/day warehousing fee.
This number of meters would probably fill most of a single shipping container, which costs around $3k to have delivered from China to Los Angeles, and takes 3-4 weeks. So from manufacture and shipping, Sparkfun would be into this lot for around $13k. If they incur no other cost and could sell them immediately, they would have a profit of $17k on this lot. We know that's not the case: they will need to be handled by their staff, sit in a warehouse somewhere, then eventually handled again and shipped to an end customer.
It would cost them another $3k to ship them back to China. Once in China, after paying import duty, their vendor could repackage and sell them somewhere else, or rework them to make them sellable in the US. Remember the vendor only sold them for $5 each the first time around and it costs them $3 to make a new one, so there's no margin after duties and repackaging for them to divert them to another customer.
If Sparkfun chose to pay for the rework, it would then be another $3k to bring them back to the US and handle them again, after a 2.5-3 month round trip, where they could attempt to sell them again at $30k, after spending another $6k+ against their potential max profit of $17k.
The money's just not there. It's unfortunate that usable product will be destroyed, but unless Sparkfun is already set up to resell in another country to which they could be diverted, I don't see a lot of options.