The feds dont want to stop it. They want to be able to tax and regulate anything that enters your lungs. Fast foward 10 years and if the earth is still here you will have to pay a per breath tax to be able to breath their air.
The last time I saw an actual figure, it was the fact that over 12 million smokers have converted to e-cigs. That has to be a considerable loss of tax revenue, if true. Soon, we will be seeing studies that tobacco cigs are not as harmful as originally thought......
Mandated walking and breathing insurance is just around the corner.