For me, Stack Exchange is the last resort for questions (I have a few floating on Stack Overflow) - after I have researched everything I can on the subject. Many times I find the answer to the question before I get to Stack Exchange - not always, but many times.
I believe that finding and making mistakes is an essential part of learning and so I try to make as many as I can before I get to Stack Exchange. Going to Stack Exchange first circumvents all the possible mistakes/learning experiences that I could have.
When I do find myself with a P.SE question, many times it requires context or is about opinions. These questions aren't always appropriate for P.SE, however, being active in chat, the questions are asked there. Sure, I don't get any rep (I get stars instead!) but that doesn't matter too much in the end. The questions in chat would have gotten closed as posted questions - too localized, or off topic (a polling question).
Realize that reputation often comes from popular questions and their answers. For these, it is about learning how to write well (an often neglected skill for programmers) and knowing how and where to research (independent of the knowledge) knowing where to look rather than knowing the answer right off the top of one's head. Having the question and answer show up on the social networks (my highest rep answer found its way to reddit and got a significant amount of rep that I'm still rather embarrassed about) can substantially boost rep. Lastly, as questions age they still produce rep - something that is a year old still pays dividends on reputation, and over time this leads to being a high rep user.
As an aside, you may also find Why always answers of users who have the maximum reputation in a question accepted and voted up? to shed some additional light on the question from another perspective.