I don't see a problem with that. It seems to me most companies sponsoring the contests have legitimate problems they wanted solved.

Now it really illustrated to me how data science is still an incipient field. Even the basic Titanic example has a lot of fake solution and a bit of "cheating" (overfitting).

And don't get me started on the multitude of tutorials and examples that only show the loss decreasing graph but the actual results are not evaluated (and thus might have some glaring defects).