You can value your inventory however you want - but good luck explaining your method to the tax man or the insurance company if your valuation does not meet industry standards.
And the industry standard for retailers is to value the inventory at retail price. 2,000 meters with a retail price of $15 are worth $30,000. That's the reality.
At the end of the day, when it all comes out in the wash, all the tax man cares about it your expenses and your income, giving you a net profit that they tax.
Sparkfun lost $10K, or whatever the cost actually was + the disposal.
If they are smart they will make up for that in extra sales some how, but that's hard to quantify. Plus of course the publicity, which is worth a lot more than that $10K in advertising, but again, that's hard (impossible) to quantify. Same thing for Fluke, this is the best money they ever spent. Again, not $30K worth, maybe $10K in inventory cost.
Start the conspiracy theories, both of them set this up as a marketing gimmick
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