For one evening last week, Mickey D’s was able to lure New York City’s foodie crowd with pumpkin-spiced “biznuts.” Now it’s trying to win over hipsters across the pond with free hamburgers.

The Golden Arches has launched a campaign in Sweden that lets people—young festival revelers in particular—swap empty cans for food. Bring in 10 cans, and get a hamburger or a cheeseburger; haul in 40, and get rewarded with a Big Mac. To promote the program around parks and festival sites in Stockholm, McDonald’s installed billboards that double as trash bags that passersby can pull out and fill up with the recyclable litter.

“These young people don’t get CEO paychecks,” says the website of DDB Stockholm, the firm that’s marketing the campaign. “Without counting their money, they only have enough for beer and maybe a little food…. Good for the stomach and for the environment.”

This isn’t the restaurant chain’s first effort to cozy up to the millennial market. A January memo detailing McDonald’s 2014 to 2016 strategy revealed a plan to prioritize coffee sales over burgers and fries to entice the Starbucks cup–clutching demographic. In May, the company hired young artists to paint minimalist ads (at least according to the TV spot promoting them) all over Paris.

So far, none of it is working.

McDonald’s saw its biggest slump in a decade earlier this month. For the majority of the past year, the chain’s U.S. locations and nearly half of its global outposts that have been open for at least 13 months have had flat or declining sales. The Wall Street Journal reported that it’s partly because Mickey D’s has been losing millennial customers, who lately have been taking their business to fast-casual spots such as Chipotle Mexican Grill.

“Millennials place a high value on social responsibility, sustainability, local, organic, grass-fed, and hormone-free offerings when it comes to dining out,” advised one restaurant consulting company, according to Advertising Age.

The McSwedish experiment might result in fewer beer cans and hungry hipsters on Stockholm’s festival grounds. But to sway socially conscious consumers, the chain needs to crank up its efforts. Here’s a good start: paying its employees a livable wage.