Just because data exists doesn't mean the disparate pieces should be connected. It would have no relevance. Data is just little pieces of stuff. Information occurs when relevant data is brought together in a meaningful form.

What happens, though, is data that has nothing to do with each other are merged into invalid information and that can be dangerous. I worked for an organization that wanted to look at sales trends among area codes. They assumed that area codes were geographic-based. They were once. Now with cell phones and VOIP, you could get an area code that is not relevant to your geographic area. That data is now useless to them.

Relevant data such as merging all of one's medical records from disparate medical sources into one view is useful. But, simply merging data together without thought is bad.