The reason is that we work on "evidence based practice". That means that until there is a study proving we can't be sued for divulging information, we keep our trap shut on our personal opinions. One lawsuit can ruin a career and quite frankly, it isn't worth it. Since there are no studies and the effects of long term vaping are unknown, you aren't likely to get many to go on board. If the patients would stop suing, we would be much more willing to use you as our experimental subjects. I VAPE because I BELIEVE it to be better than smoking cigarettes, but if I were to recommend it to you and you had an allergy to whatever you could then sue me for your bad reaction and promoting an unproven cessation device. Until it is "approved" by our facility, you won't see us putting our necks and livelihood on the line. There are some hospitals that do allow it in the units, and some forbid it within their walls.
Sorry, that is the hard facts. Society is too litigious. Get people to stop suing us for trying to help you and we would.
To the student who is reaching out to patients without a license, I applaud you for your efforts. I also warn you to get some good malpractice insurance and read your coverage very carefully.