This makes sense, unfortunately. The e-cigarette industry is $1B+ and much of their base from teens, they can claim to be innocent by not marketing to them. However, with flavors like bubble gum and cotton candy, it is easy to see why teens are attracted to e-cigarettes.
I used to remember a lot of anti-smoking ads on tv but no more now. You need to run ads for each new generation of teens. The same for ads against bullying, racism, drunk-driving, drugs etc.
As a late-teen, I see many ads from the FDA against e-cigarettes, but I'm not sure how effective they are. However, these are not on TV but on Facebook.