[shoo]

they are also problematic in that they discriminate against people who don't have a bunch of time and energy to spend on something that isnt guaranteed to have a payoff.

e.g. people who are struggling to make ends meet and need actual work that pays cash, or people who have a bunch of responsibility with very little time (family to look after)

that said, such people are also disadvantaged in the workforce generally as they may lack the free time and money to be able to pursue opportunities for better jobs to help bootstrap into better circumstances, so it ain't something hackathon specific.