What would be the one and only incentive to apply? Power. Ego. Bragging rights.
Don't give me the 'We do it to better the community', 'We do it because we love the game so much' I don't buy that. If that was the goal we would not be having these problems.
How is there bragging rights if they don't reveal who they are in game?
Personally when I post my simple guides or charts, I don't do it for an ego trip. Yes, it is nice to hear that people read it as work was put into it, but with my relatively low expectations, I generally expect most to ignore what I write (hoping at least one or two take a look). In the end though what I write is mostly as reminders for myself and if they helps others, then kudos to that.
When I worked retail, while of course a company likes it when you are helpful, but when not payed in commission, you don't have much intensive. I still took the time to learn all there was about what I was selling so that I could help people find what they are looking for or something that would fit their situation. I did that as extra with no bonus and maybe only a thank you here or there, but I still did it for others. I could have been like other employee's that I worked with that barely knew what they were selling and generally got the same hours and pay (evil retail....), but I didn't.
Now of course I only talked about myself there because that is who I know. Many people have their own circumstances and I'm sure you're not completely wrong in that some people love to have their ego's stroked, but to say that everyone is like that is a bit narrow minded.