The first rule of drinking is "know your limits" -- including the limit of how much booze you can reasonably expect to sneak past security at a sporting event.
Judging from the jerseys he and his colleagues are wearing, the man is a fan of Göztepe, a soccer team based in the city of Izmir.
What gave our parched protagonist away? Maybe it was the long coat and scarf, while everyone else is wearing T-shirts. Maybe it was the bulging beer vest underneath, stuffed full of two cases-worth of brew. Or maybe it's the sweat he keeps wiping off his forehead, presumably from either nerves or wearing such a heavy coat.
Of course, his friend wonders aloud if he was able to sneak the beer in, and that doesn't exactly help the situation. Per a translation by The Huffington Post, after the smuggler is caught, someone in the crowd says, "I'm literally hurt seeing this. The beers are gone."
Better luck next time, friend.