There is a difference between ultra-light touring and ultra-cheap touring. I have met people doing the ultra cheap thing, camping in people's back yards, or sneaking in to campgrounds and out again without paying.
If you are gong to be ultra cheap and NOT sponge off people, then you probably can't go ultralight as you would need camping gear, cooking gear (probably), all those things that add up the weight.
I really don't see the big deal about light weight bike touring - I can see it in backpacking or ski touring, where the weight is on your back. A few extra pounds doesn't make a huge difference on your bike and if it makes you more comfortable, then why not?