Pretty much all of forensics isn't real. Blood splatter analysis, polygraphs, fingerprinting. That doesn't mean it doesn't put people in jail.

What, specifically, are you claiming is “not real” about fingerprinting?

  Their use as evidence has been challenged by academics, judges and the 
  media. There are no uniform standards for point-counting methods, and 
  academics have argued that the error rate in matching fingerprints has 
  not been adequately studied and that fingerprint evidence has no secure 
  statistical foundation. Research has been conducted into whether experts 
  can objectively focus on feature information in fingerprints without 
  being misled by extraneous information, such as context.
  

https://en.wikipedia.org/wiki/Fingerprint

There's a common belief that fingerprint analysis is objective and reliable, but there's a great deal of subjectivity involved. Additionally, there have been several convictions involving fingerprints as evidence which were eventually overturned.

While they may still be useful, they have an image of infallibility that doesn't line up with reality.