Why are Venezuelans posting pictures of empty shelves?

http://www.bbc.com/news/blogs-trending-30710014


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BBC Trending have established that it all began on New Year's Eve, when photographer Alejandro Cegarra stood across the street from a branch of the Excelsior Gama supermarket chain. He was trying to take a shot of the many long queues outside the store. He was approached by officers of the National Guard who ordered him to stop, and he live tweeted about it - capturing the attention of hundreds.

Translation: "@Excelsior_Gama unless your policy is to attack a journalist with the National Guard, speak with the manager of Santa Eduvigis branch" Translation: "@Excelsior_Gama unless your policy is to attack a journalist with the National Guard, speak with the manager of Santa Eduvigis branch"
The supermarket manager then also approached Cegerra and told him to stop taking pictures, even though he was not actually inside the premises. Then, as Cegarra also tweeted, the manager asked a National Guard officer to arrest him.

"Another person claiming to be a journalist from newspaper El Nacional came to my support," Cegarra told BBC Trending. "He warned the officer that if he was planning to detain me, then he would have to take him too."

By then, his comments had been retweeted hundreds of times. Excelsior Gama subsequently apologised to him for the incident, but that didn't stop thousands of others posting pictures of empty shelves as a form of protest.