Earlier this month, Swedish sportswear retailer Bjorn Borg and agency Nord DDB debuted a trippy film comparing the elation you get from exercise to the highs you get from drugs, as part of its new “Chase the Exerhighs” campaign. Now, to carry out the idea into the real world, the brand opened a retail shop in which shoppers could get their hands on limited-edition Bjorn Borg pieces--by paying with their drugs.

At the pop-up in Amsterdam, Bjorn Borg told shoppers they could swap their weed, pain killers or other stash for limited pieces featuring illustrations by Patrick Saville, whose ‘70s-style art also evokes the feeling of a dreamy, tripped-out state.  At first, some scratched their heads, but eventually returned to make an exchange.

According to the agency, it confiscated all the “payments” by burning them, but unfortunately, didn’t do any analysis whether any of the drugs were of the illegal sort.