I'm not sure if it's a bug or a feature but whatever it is, it shouldn't work like this.
When we click on the type of reward, the options come right beneath the header.
Adding to that, the decline payout option isn't there.
Uploading a video so you guys can look into it.
How to Reproduce This Bug
Open utopian.io
Click on any contribution you want to add
Select the type of reward you wish to choose
Device: Lenovo G50-70
OS: Windows 8.1
Browser: Google Chrome, Firefox
Posted on Utopian.io - Rewarding Open Source Contributors