FAA rules forbid any pilot from consuming ANY amount of alcohol in-flight! Your passengers may open a bottle, but as the pilot, you must stay awake, sane, and sober. If you must pass control to a passenger, he must be sober also. I hate to say how many mid-airs that African air carriers suffer because of drunken or stoned pilots. Catch a downdraft or wind shear, and your reaction (and judgment) will be way off. Calm-air turbulence (CAT) has claws!
Airport security rules apply to private aircraft when they use that airport. Regs at LAX are somehow a little stiffer than when you land at Love Field in Dallas. DFW gets all the airlines, but Love still handles nonscheduled flights.
When you file your flight plan, know the regs where you plan to land and know alternate landing strips along your route: many do not have flight control.
Always observe the "eight hours from bottle to throttle" rule. It will save your license -- and your life.