So but, I find heavenly bliss when starring at beautiful markup. Is there something wrong with me?
There's another word for it -- professionalism.
To get serious, um, just for a moment, well formed markup has all of these advantages and I'm speaking very, broadly i.e. coding as well since often it's embedded in markup:
Readability
Easier to debug/trace
Best standards compliancy
Validation to W3C and other standards
Portability <--- well formed RE-USABLE code/markup = life is good
Efficiency
Security <--- if you don't grasp this, imagine, say, tracking a hack in 10,000+ lines of source not following any of the above
But most importantly, it means one very important thing to me:
INCOME.
ps: To DIY or newbies -- only need to really focus on the first two, the rest come after screwing up badly which is inevitable. So a solid two hand golf clap for 960design.