Is that reliable though? I'd imagine the DEA is more likely to investigate a dealer declaring their location as Washington DC than one declaring Netherlands. So their is a definite incentive to falsify this.
But a buyer from the US is far less likely to order from the Netherlands since international mail goes through customs and there's no 4th amendment protection on them at all.
The majority of the buyer are going to buy on feedback. And a US supplier using fake Netherlands location is likely to get good feedback based on fast shipping (seeing how its fake Netherlands) and gain the benefit of the "positive" Netherlands connotations (Hollywood's view of the Netherlands in the average person's eyes).
4th amendment - true but not relevant to an environment dominated by non-lawyers and buyer's reviews I think.