The City of Maastricht is battling the European Union over whether it can prevent drug tourism by having “coffee shop” sales restricted to Dutch citizens. If the EU rules that Dutch coffee shops cannot deny cannabis sales to people from outside of the Netherlands, Maastricht may follow the lead of other Dutch border cities, which have simply closed their shops to get rid of drug tourism. The EU’s push for policy harmonization could thus lead to more restrictive cannabis policies in its member states (even as it has tended to open up access to alcohol).
One might wonder why the Dutch would not want drug tourism, given that governments normally do their best to lure tourists to visit and to spend money. The coffee shop owners of course want drug tourists and the profits they bring. But the rest of community endures more costs than benefits.
The central problem with drug tourism is one of selection: People who will travel even an hour to use drugs are not a random sample of all drug users. The same principle applies to all those Brits who fly RyanAir to Spain for all-you-can-drink weekend promotions at budget hotels, and the U.S. college kids on spring break who are drawn to similar offers in Mexico. Cannabis users as a population are not particularly prone to vandalism, disorderly conduct, and petty theft, but the subpopulation of users that will take a trip (no pun intended) for cannabis often commit these crimes, creating nuisance, distress and policing costs for locals.
A further cost to the country that attracts drug tourists is how more serious criminals respond. If you are a dealer in cocaine or methamphetamine, and you want to efficiently access a pool of probable customers, border towns with drug tourists are attractive bases of operations. There you will find many young men who are by definition unusually interested in using drugs and are away from whatever social constraints and norms surround them at home.
If California legalizes marijuana, drug tourism would be substantial in border communities as well as in cities with budget airline service. Being free from EU-like constraints, the state could try to reduce such tourism by limiting cannabis sales to state residents. This however would make only a marginal difference unless state residents had a cap placed on how much cannabis they could buy (else they would simply buy a large amount and turn around and sell it at marginal profit to out of state drug tourists). It would not be impossible to build a fairly strong regulatory system, but the needed policing would cost money (those putative savings of Proposition 19 are looking smaller all the time) and because the system would be imperfect, at least some California communities would endure the externalities of drug tourism that the people of Maastricht are facing now.