I believe the way it works in Portugal, if you're caught with drugs you are required to attend a meeting with Justice of the Peace, a Lawyer and a health care professional (psychologist). In other words, they offer the addicts help instead of giving them a fine and/or throwing them in jail. Make total sense.
Both here and in the US, the premise is to arrest everyone who has illegal drugs. It's been like that for decades and we aren't even close to winning the war on drugs. As the saying goes, the definition of insanity is doing the same thing over and over and expecting a different result. And that's exactly what they're doing.