We do not force people as it is not a requirement to join our forum. I usually read back through some of the posts and add their location if it has been mentioned in any of their previous posts. Some people are uncomfortable for a variety of reasons posting their home location and having raised a child in this world of the internet,I can understand.
When someone makes a post and we ask them to add their location,thats as far as it goes. The choice is theirs and most make that choice when filling in the forum profile info when they join. The info spot is in the same general area where you put your username.
We have not made a big deal when you changed username when I could have reset your password,so I don't take too much issue when someone opts not to add location.
Be patient with these people, most problems can be solved/shared regardless of location,even if some are more locality specific.