its not just expensive bikes that people lust after, just off the top of my head, golf clubs, jewelry, headphones/speakers, watches, purses, shoes, tv, even clothes.

everyone knows that what they get in return for their cash isnt even close to being proportional, but thats ok, as long as you can afford it and it makes you happy.

a 6k bike will have marginal improvements over a 1500 bike, which is easily taken away by an extra bottle of water or a flappy jersey, but if it makes you feel good and gets you to ride more then why not?