Yeah - I know it's an old thread, but it's something I've thought about.
I have one of these (see link below) which I plan to use on the riverbank/beach. I have thought about using it in my intended SIB but I think it would be too much of a squeeze and I would have to support the legs on the airdeck.
It's a joy to use though, roomy, off the ground and very comfortable.
https://youtu.be/Pzjm4nT9bxo