One needs to accept that nicotine is an addictive drug, a legal one, thus try telling a cocaine user, an addicted user, that he can't have his intake, upon what he is so dependant, for a number of hours.
Whilst smoking is banned in many public and work places there remains a facility, for the majority, to step outside into the fresh air for their cigarette. A pilot, or indeed any crew member, is denied such a facility thus it should be understood that they are addicted to this drug and a compromise should be found.
P.S. I am not a pilot nor a crew member but I am a smoker.