If your business is in one of these states, you cannot factor an employees legal use of tobacco (and in states like Arizona, California, Pennsylvania, New Jersey, and Nevada, their legal use of marijuana) outside of the workplace into your employment decision making process, whether thats during the hiring process or otherwise throughout the term of their employment
An infamous quote from one tobacco industry document gives insight on how they view recruitment: "Younger adult smokers have been the critical factor in the growth and decline of every major brand and company over the last 50 years
However, the nicotine provided is minimal, so observe your usage levels, as you may find that in order to achieve the same satisfaction as your old cigarettes, you may end up vaping a 3mg e-liquid at an excessive rate
Simplechoice, cost (sometimes), and curiosity