Cotton, whether it's waxed or not, is heavy and absorbs water into the fibers.  Cotton is also not durable long term, and will show signs of wear after a few uses.  We developed our upland pants to catch up with what every other outdoor industry was already using.  We combine lightweight fibers with high durability fabrics and DWR treatment to give you a comfortable pant that will last longer that any traditional pant on the market.  You won't want to take them off when the hunt is over.