Bike Companies have to sell bikes. Period.
If the latest model is lighter, more aero, and looks a little more funky (fugly) it attracts attention.....knock on = sales.
Without Freds (or whatever other label you attach to those guys & girls who spend plenty of $$ on the latest and greatest gear) the bike industry would struggle.
What do you call those guys and girls who drop a quarter Mil on a massive 4wd SUV unit and can't even change the tyre, let alone drive it off road??
Some folks have plenty of cheddar, and don't give a f@#k what they spend it on, and least of all what you think of them -

More people on bikes is a good thing. Period. If it's a 20K machine with the full monty Specs and they ride at 20 kmphr for less than 50kms per week in full Team Kit...so what?? They're spending money in the industry = good thing!
Pro's don't buy their bikes...they're paid to ride the sponsors bikes. Riders like Cav etc are actively involved in R & D for their sponsors bikes...albeit to make them go faster, be more comfortable, etc...this trickles down into the general population of bikes over time.
Some riders (Freds perhaps) like the thought that they have the same bike as (insert Pro rider of choice here).
Internal Cable routing, integrated headsets, integrated stems / bars, electronic shifting etc, etc it's all just a sign of the times whether you like it or not?? You don't have to buy that stuff....you have options, loads of them.
I'm not a huge fan myself. I ride Ti and Steel and like mechanical shifting and the more classic fit out.
Mechanic's need to keep up to date with the progression of technology and design in the sport. Surely a change of scene and a new challenge is welcomed? Sure, more tools and different techniques / skills need to be acquired.....but that is what it is. Working on the same stuff week in week out must get a little boring.
Personally, I like a new challenge, figuring out the new tech and then being able to master it.