The carabiner/swivel is to connect the chickenloop to a climbing harness.
We are a few of us, only using a climbing harness for snowkiting.
We are wearing it under the snowpant.
It's a lot less heavy than the kitesurfing harness.
Better for walking in the mountains, or coming back with skins when the wind dies, better for skiing, better foreverything in fact.
The main reason is that normaly snowkiting is not kitesurfing on the snow.
They are two very different sports, as different as surfing and snowboarding.
Even if a lot of snowkiters make the same freestyle moves on snow and water.