Buying and selling gmail invites is a great promotional tool for google.
It only hurts them in the end.
"The changes are designed to deter people from creating multiple e-mail accounts with the purpose of reselling or trading them, according to a source at the company. The policy alterations do not target people trying to barter Gmail invitations, which allow people to sign up for a new membership."
For you to make some money on selling the email invites is wrong but to barter (give them away without the exchange of money" is fine.
Interesting.
Huseyin