Just to balance things out......
I love to take these camping with me, inside my tent. That way, when I get up in the middle of the night or early morning to take a pee, I can slip something on my feet and then slip them off again before I get back into tent. This is especially useful at a beach where I don't want to track sand back into tent and have my sweaty feet soiled with sand. They are easier and quicker to slip on and off then a shoe, which would also work, and they take up a minimum of space. I always pack them in my kayak on overnighters.
As for keeping feet dry while in kayak....I don't know...my feet get wet from sweat. If its warm out, I paddle barefoot.
I wore my SealSkinz Water Blocker Socks for the 1st time only to discover that one completely disintegrated and fell apart (a large piece separated from the sock) while being worn on my feet. When I removed them and turned them inside out to see why they were wet and felt rubbing on my feet, I discovered that the plastic-like membrane had peeled off. I wrote email asking for refund and my letter was never even acknowledged.
This is without doubt, the absolute worst piece of junk on market. Never ever again will I consider any of their products and when in store, will advise anyone near the rack to stay away. Pure crapola!
My Sealskinz "Water Blocker" socks didn't even last one use before they started leaking. They were great at holding the water IN and my feet looked like dried up prunes after I pulled them off. The plastic membrane lining was shredding after just a few hours. Fortunately the weather was warm so I didn't suffer from cold feet, only wet feet.
I was able to get a credit from the store and bought some Chota Mukluks. The Mukluks I recommend highly. Stay away from the Sealskinz.