Its not inconsistent to have both sides of the topic being looked at. That the author of the piece brought into question the tax/financial aspect of the move to legalize marijuana in a piecemeal fashion is ... germane to the article. I am not sure that the Constitution speaks directly to the question of the legality of marijuana although it does limit the ability of the Federal Government to make and enact laws. I believe the phrase is; All Other Powers not Granted to the Senate are to Remain with the States ..." (OK so its not a quote).
Marijuana was painted as a "bad" item by Anslinger and Herst mostly on racial terms. They deliberately created a hysteria and destroyed an industry. (Cordage - making rope).