I can't really fault them for not knowing the difference between a provari, evic, or itaste mvp, or even knowing what they are.
The OP said the cops knew enough about them to say that people use them for contraband.
This attitude among LEOs that citizens need to prove their innocence is a DANGEROUS trend. The burdon is not on US to prove that what are doing is legal. The burden is on THEM to establish that someone was doing something ILLEGAL, and to do that, they must first have at least a "Reasonably Apprehendible Suspicion", to even detain and question someone.
And "Probable Cause" to detain people, search their personal effects or seize their property has a MUCH higher burden of proof.
Vaping is NOT a crime, any more than having a pack of cigarette papers. Without some other cue that something illegal is going on--furtive movements, trying to hide objects, inconsistent answers, physical symptoms of intoxication, etc--they have NO legal ground to stand on for harassment of vapers.
We need to educate LEA's about vaping. Get some CASAA material and make an appointment with your local Sheriff and Chief of Police, and let them know it might be a good idea to educate their officers about ecigs, because it is a FAST growing phenomenon.
IF that doesn't work, then we need to play hardball. Get badge numbers and names (and preferable cellphone video recordings) if you get harassed for having an ecig or PV. File formal complaints. Get a lawyer to send them a notice that they have been given CASAA material, and therefore they KNOW this is legal, and if they continue to harass vapers, they will be getting subpoenas to defend their actions in a Federal Civil Rights violation lawsuit for "harassment under color of law".
LEOs listen to TWO things, and two things only--orders from their superiors, and threats of legal action from attorneys.
If we educate the first group of people (LE superior officers) then we won't have to get the lawyers involved. But sometimes thats what it takes.
We need to stop tippy-toeing around on this issue, and STOP apologizing to cops for something that is 100% legal.
Vaping is not a crime...