I once worked at a major big box retailer where somebody came up with a visualization that purported to show, for a given product category, purchases made in other categories. One surprising purchase correlation was customers bought TV stands after buying DVD players. So, this nugget was trumpeted at countless meetings about the value of big data analytics. Multiple marketing campaigns were designed around this disco…
If you look at the most "controversial" data science paper from 2013 where a study correlated intelligence to Liking the Facebook pages "Curly Fries" and "Thunderstorms" (here is a summary: http://www.wired.com/2013/03/facebook-like-research/), there were a lot of proponents saying that there was no causation, and the correlation was not founded, etc.
Of course, you would say the study "makes no sense". Intelligence can't be predicted by Facebook Likes. There is no correlation there, etc. But why not? If you read the paper (http://www.pnas.org/content/110/15/5802.full.pdf) their logic is sound. Is the marketing campaigns that the company bought based on the TV StandDVD Player connection any different than other marketing campaigns? Facebook does all of their ad display based on similar data analysis as above, and it seems to be working for them.
Note: There is the not-so-hidden machine learning feedback loop now (explained better here: http://www.john-foreman.com/blog/the-perilous-world-of-machi...), where people Like the 'Curly Fries' and 'Thunderstorms' pages because of the research.