Regardless what Constitution-ignoring socialist FDR's activist justices wanted everybody to think about the scope of Congress's Commerce Clause powers, and with the exception of federal entities under the exclusive legislative control of Congress evidenced by the Constitution's Clause 17 of Section 8 of Article I, the states have never delegated to the feds, via the Constitution, the specific power to regulate intrastate commerce. This is evidenced by the following excerpt.
State inspection laws, health laws, and laws for regulating the internal commerce of a State, and those which respect turnpike roads, ferries, &c. are not within the power granted to Congress. (emphases added) Gibbons v. Ogden, 1824.
So the idea of the federal government wanting to ban sales of electronic cigarettes to minors, while arguably a good thing, is nontheless outside the scope of Congress's Commerce Clause powers imo. The states need to legislate such bans under their 10th Amendment-protected powers until they choose to amend the Constitution with such a prohibition.
Unfortunately, many freepers don't care about constitutionality, if their ox isn't gored.
/johnny