That's true! The reward depends on the allocation of the campaigns.
Take a look on
DIA bounty campaign managed by bubbalex. The amount allocated is
100,000 DIA (0.05% of the total supply), tokens price during sale was 0.05$.
On one hand this is not a biggest amount allocated in bounties. But on the other, todays token price is already $2.74. Bounty is not yes distributed, but if the price keeps the same (or even grows), it will be counted as one of the profitable bounties for hunters this year.