For me the price isn't about the weight, it's about me commuting in a city with huge hills, rain, and long flat stretches. My commute goes up and down several 300ft hills and across a long bridge (Seattle to Bellevue). So I end up riding a road bike with a large gear range and disc brakes. This isn't easy to setup, and my components cost more than the frame. When you commute every day 45 minutes each way, it also makes sense to spend some money on comfort (I mean that's 400 hours a year you are on the bike). Most people do it when they buy cars, it's the same think.
