It says on Wikipedia:
Some tournaments utilise a bidding system for individual players of each match to decide how little time they would be willing to play with as black. The player with the lowest bid for each match receives the black pieces with draw odds. This system minimises the perceived unfairness of Armageddon time controls that are decided in advance before a tournament with colours randomly allocated. Such an idea is reminiscent of the logical use case of fair cake-cutting.
I haven't heard of fair cake-cutting or more generally fair division before this. How is armageddon in chess like fair cake-cutting? Is bidding for lower time like bidding for a smaller quantity yet high quality slice of cake or something? Eg Smaller piece but has strawberry on it. So in this case:
smaller piece = lower time + black
strawberry = draw odds
If a cake with a selection of toppings is simply cut into equal slices, different people will receive different amounts of its toppings, and some may not regard this as a fair division of the cake.