I wrote a GA for picking an optimal Fantasy Football (soccer, Brit here) team based on player scores from the previous season(1). The team did above average, even though it was hobbled by the fact that I didn't do any transfers after the initial pick.

The knapsack problem(2), of which fantasy team picking is an example, is a classic use case for genetic algorithms.

1) https://github.com/chrxr/ga-prem-team/blob/master/scripts/ga... 2) https://en.wikipedia.org/wiki/Knapsack_problem