As part of improve the email address privacy facebook hide your personal email address from your profile and @facebook.com contact info is the only one visible to people with permission to see your email addresses.
Facebook made this change without make any notification to the users and this makes it harder for friends and clients to contact you via your personal email unless you reset it back. I think, users to determine the information in their profile about how they want to be contacted, not the Facebook because most of the users preferred their contact info should be personal email address rather than facebook messaging system.
Changing the e-mail account listed on your Facebook profile will only take a few minutes by following the below instruction.
1. Login your Facebook account and go to your profile
2. Click "About" and scroll down to "Contact Info" then Click "Edit".
3. Click on the circle next to your Facebook email address and change its setting to "Hidden from Timeline". and Click on the circle next to your other email addresses and change their settings to "Shown on Timeline".
5. Click the Save button. That's all.
Share this with your friends and colleagues who are not aware of this and post your comments.