The associated social accounts are not the accounts you will be sharing your clips to, but rather a page/account that your video in the below instances will be associated with. To make it a little simpler to visualise, have a look at the screenshots below.
Facebook: In some cases when a Grabyo video is re-shared onto Facebook, it will have a Facebook page associated with it. This means that the name of the page will appear and link through to the page when clicked on. If you don't enter this information, then the name of your campaign will appear instead with no click through link. In the example below you can see that FIA Formula E have re-shared a clip from Mahindra Racing.
Twitter: When a video card is selected, the sharing account will appear along with a smaller logo of the associated account just above the video. This is also a clickable link that will take you back to that account. If this field is left blank it will default to the Grabyo logo. In the example below, the FIA Formula E logo appears at the top as they are sharing the Tweet, and you can also see the associated account, or the account where the video was originally posted, which is Mahindra Racing.