See the llamas looking at them weirdly at 2:10? That's because the llamas know how ridiculous it is! I'm not just referring to how it looks, I'm referring to the fact that in anything other than nice terrain it just doesn't look like it'll work. Fancy pulling that through a marsh? Even assuming the ground is solid (big assumption in the wilderness) the video shows a pretty immense amount of struggle going through a simple gate, with a style or tight kissing gate it's going to be near impossible to manage. The webpage says you can put it on your back, yes, but then it looks awkward and unwieldy - and if you still have to put it on your back, what's the point? It also costs the earth, could well get a puncture on rough terrain, and perhaps most inconveniently takes up both your hands, meaning you couldn't use both it and a map or GPS on the go.
Seems like a gimmick to me. If you felt you needed the extra weight it provides, I'd first ask the question as to why you couldn't fit this into a rucksack, what your aim is, and then work from there. Sometimes, planning to cut down on weight is a fun part of the whole experience!