[Roscoe]

Who decided there is some magic line at which a sufficient quantity of something becomes "commerce" even though it is not being bought, sold, or traded?

Massive amounts of illicit drugs are being "bought, sold or traded." Congress and the states both typically set different penalties for possession of different quantitities of illicit drugs.

[tacticalogic]

Massive amounts of illicit drugs are being "bought, sold or traded." Congress and the states both typically set different penalties for possession of different quantitities of illicit drugs.

That still doesn't explain the logic that says if some of a particular item is bought, sold or traded, then all of it is commerce, and all of it is interstate.