there is no excuse for a pilot to drink and then fly.
BUT:
Many people simply don't know the stress involved with flying. Looks glamourous and sort of nifty. And even though booze and pilots have been around as a topic for many many years, I am afraid things might even get worse.
Back in the good old days, a pilot had a fair amount of time off duty to have some sort of life with his family. Scheduling has gotten nutty and you end up spending 28 hours in a hotel somewhere. You worry about your pay, pension and all sorts of things
throw in any tendency for alcoholism and bang...you have a cocktail waiting to be stirred and not shaken.
Sadly too, though unconfirmed, I think pilot suicides are on the rise...not in the cockpit mind you (though some questions about some crashes).
Add percription pain killers to the equation, emotional disturbances and it is something to think about.
Especially if we ever go to one pilot airliners! (hey, why is the dog barking! :-) )
j