My take on it all,
I love buying expensive gear because (usually) high quality materials outlast or out-perform cheap rubbish: Halfords GT & Cervelo S2, Dura-ace or Raceface, Gore jackets or peter storm, Icebreaker or Aldi ‘knitting’…that kind of thing. I agree there are exceptions but one catches one’s drift.
Aesthetics, why the hell not? I like to think of it as an alternative form of art. My bike is quite understated (I’m going for subtle matching) but some of the guys/gals really bling-it-up – I love it, sign of character and individualism.
On the clean bike issue, my bike always receives a royal wash and buff for two reasons, 1) I’m anal, and 2) I once returned from a ride years ago to find a whopping crack where the seat-tube weld meets the BB (cheap Claude Butler). Just imagine taking that out again with mud all over it! A&E please sir, don’t spare the horses.
QED