Not to be too contrarian, but I'm a 45 year old developer whose (basically) only code that is currently in production is what I've made in the last year. Code is generally eventually thrown away, whether it's garbage or not.
I'm not against throwing code away. I'm just not sold that the results of hackathons provide value.
Some code is doing useful work after 30 years, some after 10. Hipster stuff is called "ancient" after 1 year. Most hackathon stuff is dropped after 2 days.