1. A team winning a few very significant awards (including second place) for pitching an app that allows you to take picture of your food bowl and tell you the nutritional content breakdown. Of course no demo was provided, and the guys fessed up that they "didn't know anything about machine learning until two days ago, but learned everything needed to make it work in that time period." No one questioned authenticity or whether it was actually a possible thing to make.
2. Another group of 10 people who ONLY made a powerpoint talking about some app that mixed traveling and tinder. When asked by judges whether they had something besides powerpoint, they said that they "are not coders, but idea-people", and that it took 10 of them to make that powerpoint.