The group of ten were protesting government cuts to social programs in Spain's Catalonia region.
Their peculiar protest was a homage to Catalonia's regional Christmas decorations — the Caganers — which feature crib figurines squatting while doing their business.
Check out Spain's crazy Christmas decorations: the Caganers.
One Iaioflauta activist said, "Iaioflautas came here to do our crap against this government that is impoverishing us".
The word 'iaioflauta' is a blend of the Catalan term 'iaio', meaning gramps, and 'perroflauta' or hippy. The group are very active across Spain.
They previously carried out an Occupy Wall Street-style demonstration at the Barcelona stock exchange in 2012.
"We don’t want our children and grandchildren to inherit a society worse than the one we've lived in," member Paco Gonzalez, 60, told the Washington Times in 2012.
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