"Consider for one moment the demand for an end to the so-called "Charleston loophole" ..."
Indeed. Consider, for example, US v. Bean:
https://www.law.cornell.edu/supct/html/01-704.ZO.html
Mr. Bean accidentally entered Mexico with shotgun shells. That's a felony in Mexico. Foreign felonies count as far as being a prohibited person, so Mr. Bean became a prohibited person. This was a problem, not the least because his livelihood was as an FFL.
He applied to the ATF for relief from disability. His application was endorsed by a number of prominent citizens including, IIRC, his CLEO. The ATF declined to consider it, because congress forbids the ATF from spending money to consider such appeals.
The appeal process is that the ATF considers the appeal, and if it denies it, the appellant can ask the local district court to overrule the ATF. Mr. Bean argued that the failure to consider amounted to a de facto denial, and went to court. The district court, and later the appeals court, agreed and granted him relief from disability.
The supreme court, in a 9-0 decision written by Justice Thomas, disagreed and reversed.
There is some very fundamental injustice in that case.