Re the ADA point, even if it were included, no one would have to accomodate the act of smoking--only the physical effects of the addiction. For instance, no one would say that an employer has to provide a way for an alcohol-addicted person to drink, only to make allowance for time off to detox. Similarly, the ADA would never require a cruise ship to enable the smoking addiction by providing a place to smoke.

It might be argued that the ships enable alcohol addiction by including alcohol and making it available throughout the ship. But the point is they would never be required by ADA to do so.