I'm pretty sure the folks who have amassed "hundreds of thousands of reputation" did it merely by answering 1000's of questions.

http://data.stackexchange.com/stackoverflow/query/105837/how...

Sure there are a few questions with highly voted up answers because they are widely useful, but there is certainly the minority of high rep earners. Even the new people who are gaining lots of rep are doing it by answering hundreds of questions.

http://stackoverflow.com/users?tab=newusers