I have to disagree with Cirno.
You can't just blame the char-op but look at the adventures themselves.
Seriously, Paizo is somewhat infamous for "slapping on templates to bypass the CR of creatures" which DO require that you have a min-maxxed character.
Hell, pre-4E announcement, one of the main complaints against Paizo WAS the excessive need to min-max your character because of the lethality of the encounters.
As another on this thread has said, I and many others didn't have this problem. So yes, I think you can blame the char-op and "EVERYTHING MUST ALWAYS BE MIN-MAXED" group.