Copenhagen Zoo staff received death threats after the killing on Sunday of the 18-month-old animal, named Marius, which shocked animal lovers around the world.
Thousands signed an online petition to save him, with a billionaire even offering to buy him and keep him in her Beverly Hills garden.
But in Denmark, a nation with many farms, an overwhelming majority of social media users felt the global outcry was a sign of hypocrisy and political correctness.
A journalist for the Politiken newspaper, Kristian Madsen, wrote on Twitter: "The whole world has gone crazy. What do they imagine the lions eat on days without a treat such as Marius? Brussel sprouts?"
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Dorte Dejbjerg Arens, a project coordinator, said: "I'm still livid over Marius. How can people get so hysterical over a giraffe while cancer, the war in Syria and the (anti-immigrant) Danish People's Party still exist."
However, the relatively muted public reaction in Denmark to Marius's death can partly be explained by cultural factors.
"Denmark was urbanised relatively late, which is why the general opinion here is that it's okay to keep and kill animals as long as you treat them well," said Peter Sandoee, a professor of bioethics at the University of Copenhagen.
"Animal rights activists in Denmark aren't nearly as strong as they are in Britain or the US," he added.