In my own understanding, stakes can be modify as shares it means you can get the amount or earning base on the total tokes they've been accumulated after the campaign period. The total number of token will be distribution and decided to all the participants base on the stakes that they have  which can be calculated like this Total token supply ÷ Total stakes of participants=  total tokens received. However, when paying by token it means there will be immediately exact number of token that already calculated and give to participants.