I think you are defining UL as "people who are concerned about lightening the pack." The UL craze is an end unto itself - they are MOST concerned about being as light as possible, to the point that they are not so comfortable as they otherwise might be.
I think most of us here fall into the category of lightweight - we value function and comfort more than being light as possible, and if a lighter item will work that's what we go with. But with a shelter or a pack, my ultimate priority is COMFORT - I refuse to compromise on the functionality and sometimes the primary function is my warmth or my comfort. A shelter NEEDS to be adequate to the task. If I know the forecast is for rain and there will be trees, I will take the hammock and tarp every time. If it's alpine I'll take a solo tent. Because if there is one thing that is NOT FUN about bivy sacks, it's being stuck in the rain, having to pee, and not wanting to get all the stuff wet when getting in and out of it.
I will never be UL. My pack is 25 lbs for most things including Search and Rescue, but I won't be caught out without proper gear.
"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzukihttp://hikeandbackpack.com