I very nearly fell prey to one of these companies. Went so far as to enter my address/name/phone/etc in a field, click next, and then it asked for a credit card. This made me a bit suspicious (Free things shouldn't need my credit card for any reason), so I reread the terms I was agreeing to. That's when I caught that I was going to be hooked into a plan to pay $80 every month for 5 cartridges. I hadn't started with ecigs yet at the time, but I knew enough to know that was ridiculous.
Despite the fact that I didn't purchase anything, and in fact left the page right then, they then called the phone number I'd entered. Not once, but three times. I was very concerned that I would have to get it changed, but they finally gave up.