Federal law enforcement vs. State laws (CA prop 64)

Hypothetically could do something akin to postage stamps.

Sale of product without proper stamp/seal is an illegal sale. Such stamps could easily be sold with no record, last I heard the post office isn’t keeping track.

IIRC, the last SCOTUS ACA decision had an interesting corollary - they agreed the mandatory insurance penalty was a tax; but also added a comment that the interstate commerce clause id not apply, whereas Obama’s argument had been their authority came from the widely overused Interstate Commerce clause. It seemed like Roberts was trying to put a lid on ICC.