Advertising revenues are based on a metric like clicks or some other form of tracking usage. Generated posts that generate more clicks is what anyone should expect in any company who's major revenues is AD based. No one knows what's real in these sites and these drive by posts are only worth posting to if you want to support the revenue stream. Could be a bot or could be a paid poster, I bet on bot for the drive bys and paid performers for the permanent PIA types.
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