[dbaupp]

What's odd is that they don't see the parallel absurdity of outlawing a piece of metal carved into the shape of a firearm

What parallel absurdity?

A number's meaning is entirely arbitrary and dependent on the context: a bit-string that is a pattern for a firearm in program A might be a perfectly valid music file in program B.

Firearm is a piece of metal that had to be precision shaped to throw small pellets of metal at very high speeds.

(I'll agree that 3D printing muddies the waters though.)