Electronic cigarettes have not been officially declared by the FDA to be tobacco products yet.
These bans are taking place because electronic cigarettes look like smoking, not because they are a tobacco product.
These bans are the result of legislation that was often written, introduced, and pushed by the ANTZ.
When we show up and fight such legislation we often succeed in having it killed or amended.
We could call them frozen bananas, and they would still be included as part of the ban attempt.
EDIT: Actually I should amend that statement
EDIT: The bans are because e-cigs threaten the livelihood of the anti-smoking zealots
EDIT: Looking like smoking is only one of the reasons, but the main reason is because they work