I would imagine they publish papers that are reviewed by other academics. It is possible to use their algorithm on a dataset without entering a contest to do so.
It's a little like asking why Electrical Engineering PhDs are not designing the new iPhone (probably some are involved somewhere, I know). Research and applications are two separate endeavors.
The researchers actually do set up competitions to see who is best. However, there are few entrants. In kaggle there are 1000s of competitors, so it's a better judge of whether they are legitimately improving the state of the art (rather than simply schmoozing their local funding agencies).
Oh, just noticed the username. I hope someone hires Marshall soon, or he finishes the book he is working on , or whatever, so this long form trolling can come to conclusion.
It's a little like asking why Electrical Engineering PhDs are not designing the new iPhone (probably some are involved somewhere, I know). Research and applications are two separate endeavors.