I think this is probably a tempest in a teacup, assuming the product actually receives approval which is still questionable, the majority of people who are found out to be drunk in one situation or another don't need to be seen consuming ...their actions usually give them away. I would assume that the smell of alcohol on their breath would still be present since they have still consumed alcohol.
Not sure. Since it is encapsulated and dissolves to release the alcohol, one could just swallow the powder (or suspended in a cold liquid) and allow it to dissolve in the stomach/intestines where the alcohol would be absorbed as usual.
(Why do images of Edie Falco's character on Nurse Jackie come to mind here?)