In fact, you have to understand that after you have participated in the bounty, you can only wait. When to pay you is a problem for the project side. In the course of this work, we have no ability to ask them, and we can only accept various conditions silently.
I also agree with you that you have to wait for sometime to get reward from the campaign as you have participated but I thing what sometimes slow down the rate of distribution is network or possibly the time take to calculate and decide on the rate at which to distribute the rewards based on the number of allocation and participants.