I think what mountainkowboy was trying to say is why have a TC when you are using it like a Class A, C, or trailer, which are cheaper. A truck camper allows you to go deep into the woods, where these other types are precluded and, as such, you should be outside and not worry about living space on the inside. So why convert the inside to being more livable with respect to adding a second living space in the cabover.
However, personally, I do go deep into the woods in the Summer, but in the winter, after skiing, we are living in the RV like a "condo in the woods." You are not going to sit outside and freeze your butt off, so making it more livable is nice.
But I agree with you burningman, some people get a TC because they a pulling, or want to fit in a standard parking space, or want a separate vehicle without pulling one. In my opinion, asking the Forum for help in making the vehicle better for whatever reason is helpful for many even if a few find it a waste.