I think it is good to get any profit from this projects, many project is fail, gain some free money is good even is low.
This type of mentality is straight-up irrational, people took out their precious time out of their lives to work in such campaigns it is not any type of pity they are doing to the participants by giving them the money they deserve.
Consider if you did 9-5 job for 6 weeks and at last you only got 1% of what was promised. Would that be acceptable to you as well? I guess, no.