At that point you can treat the actual issue, not the substance.

Alcohol is illegal to inhale in some areas. Not others.

http://en.wikipedia....ol_without_liquid

The delivery mechanism is what makes it illegal.

We already live in a world with many laws like that.

My flavored rolling papers are illegal if they are sold with tobacco. Federal level. But it is not illegal when sold alone, or with "legal" herbs which can kill you.

Buy any can of paint or solvent and you will see it various illegal uses.

Oh well.