Manufacturers sometimes have vastly different pricing based on region and want to protect profits, to the point that most (all?) manufacturers will not service "gray-market imported" lenses in the US. So large 3rd-party grey market importers like "E-Infinity" even offer their own warranty.
Like ashen-faced children, slaving in a sooty factory, under a leaden sky.
What is grey-market again?
Brilliantly stated insight, by the way.
Black market is also drugs, guns, ... any trade not official allowed. And stolen goods often get sold legal via ebay, craigslist etc.
Some people report that after providing receipts to the rights owner they got unblocked.
Also see Blazer v Ebay, where it appears that Ebay (in 2017) was not really jumping to take down items on a whim.
It's also very hard to tell whether genuine goods contain illegal lead paint. When Nikon and Apple products get pulled from shelves based on an unsubstantiated email from my lawyer, I might show some sympathy to their crying wolf about counterfeits and stomping over consumer rights.
If they were found to contain lead or anything harmful, the stores could be liable for facilitating this or that crime - the courts ruled the police do not have a duty to protect, but apparently retailers do, and must act with the presumption of guilt on the most spurious of allegations.
Sure this will make commerce impossible, but we had no issue making commerce impossible for individuals, did we? We just treat them as fly-by-night Chinese importers, even when they're based in countries that very much put people in jail for counterfeiting and eagerly cooperate with various IP prosecutions. What's good for the goose, is good for the gander.
It appears that currently if mostly affects legitimate sellers and facilitates despicable differential pricing, but in absence of such rules the picture would likely have been different.
Also manufacturers face hefty criminal penalties for declaring a safe product and selling lead salts, what kind of penalty can be levied on a Chinese shyster?
Also-2, retailers can and are held liable for selling dangerous goods, see Schwartz v. Macrose Lumber.
Which rules? There is no law forcing Nikon to act this way. They do it purely for profit. Suggestions that they'd be somehow liable if they don't police their consumers are beyond tenuous.
Granted Nikon is a Japanese company, but preserving a company's good name and consumer good will can also be seen as a duty to shareholders. In other words, they are not legally compelled or even legally incentivized to act this way. They are only, as you say, allowed to act this way, which is not any kind of excuse.
Why doesn't the principle of being presumed innocent until proven guilty apply here?
This assumption doesn't work that way in Haiti or El Salvador - you have to allow for hostile intentions of strangers or you'll get burned.
In a more benign plane, presumption of innocence allows you to pay strangers upfront and expect delivery of what you ordered. You can only do that because there are stiff consequences for misusing this trust.
The presumption of innocence in a legal sense is the principle that any person accused of a crime is innocent until they are proven guilty. It is the most fundamental principle in any system of justice, and I still have no idea why you think it is the cause of any problems in El Salvador, or why you think implementing a presumption of guilt would change anything.