Good question! Yes, the licenses and the terms of this hackathon keep the IP ownership with the creator of the software. The choice to require open source for hackathons is ultimately up to the sponsor, but is generally with the goal of enhancing the open source community. After the winners of this hackathon are announced, you can always choose to make your code private if you prefer.
By forcing us to make our code open source, you are forcing us to surrender the IP into that Open Source contract. Even if we edited the Open Source contract to require payment for the IP, this is both hard and expensive to enforce.
Basically, if anyone develops anything interesting, Google get to take that idea or code and use it as they see fit. And all it cost them is $24K.
As such, We will not be submitting our project unless this condition is removed. If they like what we did, they would be free to contact us and discuss purchasing our IP, however I am not giving it to them for the chance to win a few thousand dollars.
Thank you for your feedback! A part of this hackathon is about showcasing community built solutions and what is possible with Google Maps Platform. If you are focusing on building a business or startup, there is Google for Startup which provides a lot of resources for startups no matter where they are in their journey. https://startup.google.com/ Best of luck with your project!