There are a lot of improvements in bike design and technology which inevitably bumps up the price. Here are some features that bump up the price:
1. Internal cable routing. This improves aerodynamic and gives a cleaner look.*
2. Sloping top tube. This gives more seatpost thus giving compliance and a plush ride*
3. We now have wider tyres which means less rolling resistance and a more comfortable ride.*
4. We have Superformed and high tensile gubbins to give lateral stiffness and vertical comfort.*
5. The bikes are very aero now. They save a massive 5 Watts at 120mph.
6. Wind tunnel testing is not cheap you know.
7. Some bikes, like Canyon, give you two handle bars. And both of those bars are aerodynamic in profile. There are no bricks here.*
8. Disk brakes with hydraulic fluid gives enhanced braking power in all weather conditions.*
9. You now have seatposts disjoined from the rest of the frame for extra comfort (how long that'll last before it snaps is anyone's guess).*
10. Some bikes have those little flap things that come out from the headtube like on some Trek bikes. This is for better aerodynamics when you are going down a mountain at a mere 50mph - it really makes a difference compared to the large rider plonked on top of the bike. Honest.*
Key:
* This is a load of BS.
Yeah, bike prices are friggin' crazy. All that crap about low sales bumping up the prices is rubbish too, and the carbon layup costs, more BS). I have all the bikes i want and I'm done with N+1.
EDIT: oh yeah, here's a good one... light weight helmets are more expensive than heavier ones. Uhm, yeah coz they have _less_ material in them. So in effect, you really are getting less for more.
Di2 is cool though. A high perforamance, actually even a low peformance, motorcycle gear system still kicks any transmission on a bike and has to handle higher power, torque and revs than anything on the highest of high performance cycles.