I asked myself that same thing all throughout my 20's.
I spent 2 years in my 20's without ever once meet a woman who was single! (not exaggerating)
Every decent girl was married or gay.
I had this mantra...
"If you're out of shape, bald, pock-marked, abusive, selfish, broke, addicted, angry, and rude, you can get the girl. If you're a kind gentleman who takes care of himself you'll die alone because women have no standards"....but I learned, through time and experience that I was totally wrong. The decisions people make are generally based on how they see themselves, and it applies to the dersirable (to women) men as well as it does to those beauties we see with the neanderthals.
Ignore the lady who wrote you first. You have made a very real observation and your frustration isn't uncommon.
Let me reccomend that you read the "Torn Between 2 Husbands" blog, and you will see that tons of women just said the exact thing you just said, but in terms of Brent (and how they are frustrated they cant meet a nice guy like him).
Its a normal frustration for both men and women. Be patient, bud. Your Lady Fair will come when you are ready, I promise.
Bottom line, dating is just hard. It requires alot of patience to find your match. Dont let your observations embitter you. Trust me, Ive been there. =)
Now I have the most amazing woman in the world and Im glad I never married anyone I met when I was younger. And one day, you will be too.