Second, there may be some issue with the vapor and books.
Many libraries have rare book collections, as well as historical archives.
Many libraries also have art collections, in the form of paintings, sculptures, etc.
I can't imagine why libraries would allow any kind of activity, including drinking, eating, vaping, smoking, chewing, etc. I've never been in any that allow any of these things, as the afore-mentioned collections I noted are all valuable and easily damaged.
I do not support vaping in libraries, sorry. Esp. where there are rare collections, which are historically and otherwise in the general scheme of things, more important to me than being able to vape while looking at them.