HOC members can choose any chapter they want to be their "home" chapter. The primary reason for the member to select a chapter is so that the member will receive communications from a Chapter Leader regarding club events in a particular area. The primary reason for HOC leadership is that your "home" Chapter is where you are counted for club statistics. This helps the club leadership in the selection of locations for HOC events, including the every other year NA Rally.
If you spend a significant amount of time during the year in multiple locations, you could join the Chapter where you would like to be "counted" and contact the Chapter Leader of another Chapter and ask to be added to his/her contact list.
Hope this helps.