I kinda do agree with you and at a same time with others:
Pros: 1) A personal and a business email could be displayed separating each email for better use
2) Displayed emails could be used and included upon sign message for better verification of the accounts and for better assurance of identity upon a hack of any account
Cons:1) Spam bomb from the members of the forum
2) Emails used to trick someone that their somebody else which could be controlled by signing a message on meta section together with emails
So for me it's really a 50-50 case scenario