My understanding was that independent game authors were writing games and making cartridges for these games which they then sold.
If I am understanding you correctly, somewhere in this chain is copyright infringement? Are people buying a cartridge, extracting the content, and loading it into new cartridges?
Is the market large enough to support that much effort and expense?
Or are people finding roms, perhaps intended for use with emulators, and loading those onto physical cartridges and selling them without renumeration or permission?
If so, is the market large enough for that to go unnoticed? My understanding was a successful new game might sell a few thousand cartridges and great success was in the 10,000 units sold area.
Being so small a market, and requiring the investment to even make the cartridges, it'd seem easier to spot this (from the IP owner's perspective) and seek preventative legal responses.
Sort of related: I know this requires some specialized equipment to make new cartridges, but do you know if they sell blank cartridges that can just be loaded with games? I am aware that some cartridges had custom chips on them and didn't confirm to any standard, like Zelda cartridges that contained memory and a chip for saving game states.
I am guessing, hopefully, that you know more about this stuff than I do.