Venturini (2019) explains:
"The economy of virality surfaced in the early 2000s when many Internet companies gave up the hope of selling contents and services and decided to maximise advertising revenues. According to observers (especially Goldhaber, 1997), such evolution derived from the inevitable inversion of “information economy.” Because of its abundance, information cannot be the scarce resource driving digital economy. Instead, as observed by Herbert Simon in 1971, its increase gives value to its opposite, namely attention".
Fake news is something that goes hand-in-hand with the economy of virality since it is meant to go viral.
Venturini, T. (2019). From Fake News, the Data Politics of Online Virality. In D. Bigo, E. Isin, E. Ruppert (Eds.), Data Politics: Worlds, Subjects, Rights. London: Routledge (forthcoming).