"Not heavy at all" is subjective to say the least...... Kelty lists Noahs 12 at "2lbs 3oz (35oz) minimum weight," which I suppose is without ridgeline and guy lines, and my HG hex 11' (lists at 5.14oz) weighs 6.85oz with ridge- and guy lines, and stuff sack.
Objectively, the HG hex is less than 1/6th the weight — more than 29oz lighter! — than the Kelty, and in the UL realm $150 for a 29oz weight reduction is considered a megamondo bang-for-buck ratio.
HYOH and pay what you will and carry what you want, but there are solid reasons that DCF nearly always ends up in a UL kit.