Over the years, we've received a number of requests from commissioners to be able to view email addresses from users in their leagues.  Due to our privacy policy, we've avoided providing direct access - however, we did create custom league pages where new users were warned that joining that league would expose their email address to the commissioner (and they could choose to either join the league or not).

To simplify the process, we've added a new league setting called 'Require Managers To Share Email Addresses' that commissioners can set to 'Yes' when they create their league.  Once set, potential league members will be prompted with the following warning:  'The commissioner for this league requires that they can see the email address associated with each league member. Please confirm that you still want to join this league?'.  At that time, users can choose to 'Join' or 'Leave' the league.

Commissioners have the ability to turn the setting either on or off, but only up until one user joins the league.  At that time, the option is set permanently to either on or off.