Decriminalizing drugs decreases a whole range of side controls. The justification of financial surveillance is because you might be using your money to facilitate drugs. A lot of unconstitutional searches are over drugs. How much money has been lost to civil forfeiture and asset seizure are due to drug laws? If drugs were decriminalized we would be a much freer society. Even if you don't want to use drugs but you value privacy and freedom, you should be against drug laws.