Back in the 1990's Canadian Airlines used to have an annual Charity flight from YYZ to Niagara Falls on A B767-300 for a sight seeing tour. The flight cost $45Cdn for a 45 minute flight. All the proceeds went to the Make a Wish Foundation. It was a great opportunity to make a donation and experience a great flight. It was fantastic for kids who had never flown before.
There was very little security at the time and the cockpit was always open for visitors. After Canadian was taken over by AC, the flights stopped.
With the increased security threats that are prevalent today, would it still be possible for an airline to offer this kind of a charity event. With the Cockpit locked and no baggage allowed on board!