Yes, I find that strange as well, particularly when some of their luggage is called "lightweight". I suspect that one reason may be that their bags are often comparatively heavy, especially those with/of leather, and Tumi don't want you to ask yourself how much weight you really want to drag around. Alternatively, given that their website completely lacks any apparent passion for their own product or for the experience of travelling, is that they just aren't very clued up about what (apart from brand smugness) would make people choose one of their bags.