Companies have successfully been able to not hire tobacco smokers. I don’t think this will be any more difficult.
I did a job this fall were the general contractor showed up completely drunk. To be productive I had to have him move 8 home run electrical wires so I could run my ducting through a joist. This was the third time I told him to move the stuff and he always forgot. The last time I told him was when he was drunk. He grabbed a pair of side cutters and started cutting the wires without figuring out which ones they were in the breaker panel so they could be shut off first. Sparks flew and he kept cutting. All of the wires were live and he didn’t really give a damn. It was quite funny to watch him on the job. Too bad the homeowner had to pay for all the mistakes he made, but the homeowner was warned.