And this chip is integrated into your new device. The only way to avoid this, would be a standard start of life vault, that is writeable once with the date and burns of the pathway to to re-write after that.
Oh you mean like every power source is designed today?
There are several engineering reasons to do that, they don't do that to spite people
And it's called capacitor (in the XXI century at least)
I suspect they do it this way rather than manufacture empty packages because there are a huge variety of chips out there with an equally diverse set of package designs. It's easier to pay unskilled laborers to sort chips into 200 different groups based on size, color, and pin count than to build a machine to replicate 200 different package types.
That's the crux. You don't buy mass-produced empty packages to put the parts in. Packaging happens by putting the IC die, pins and bonding wires which connect them together inside a mold and filling it with plastic.
It's probably cheaper and certainly lower-tech to replace markings on existing chip than produce a new one.
It's not clear whether the ones you can buy on eBay or Aliexpress are simply older models (and the manufacturer then removed this coating), or are actually knock-offs. We have no way of really knowing.
It was a good lesson: most of the time it's just not worth it especially if you're not chasing pennies on your product margin.