They are sewn on with large stitches. I taped the top and bottom ones to smooth the edge of the grosgrain. Of course you can flip the pad and they are on the bottom, but for tent camping (or on thin ground sheets) I don't want anything with hard pointy edges under me when I squirm about in my sleep. They are out of the way enough anyways. I like how fast it is to click them together - painless.
Funny you should mention the bit about attaching a quilt - I just finished our two person quilt and was debating for a while whether to make it click in to the pads or not. I opted not to for simplicity and time, but it is a good idea.
Thanks for the input.