Maybe in the case of magazines they have legal motivation to prohibit it, but there are many prohibited firearm accessories for which that isn't a plausible exp

Maybe in the case of magazines they have legal motivation to prohibit it, but there are many prohibited firearm accessories for which that isn't a plausible explanation. For instance they forbid ejection port covers. I think this is probably because they often have edgy shit written on them: https://duckduckgo.com/?t=ffab&q=ejection+port+cover+&iax=images&ia=images https://duckduckgo.com/?t=ffab&q=ejection+port+cover+&iax=im... Such ejection port covers have been the subject of public controversy: https://www.aclu.org/news/criminal-law-reform/youre-fucked-acquittal-officer-brailsford-and https://www.aclu.org/news/criminal-law-reform/youre-fucked-a... Also, they explicitly permit the sale of some items which have geographic restrictions, such as airsoft guns, replica and toy guns, and night vision or infrared scopes. I think these are probably all county wide restrictions rather than state specific (night vision cannot be exported due to ITAR, for instance), but I could be wrong.