At least three or four years ago, crew purchase was six miniature cans for about 90p. Bottles of wine, tins of beer/cider and miniature spirits were also at heavily rebated rates. The obvious benefit to BA was that as long as crew have purchased it and had a receipt, there was no problem. If they had taken it off and no receipt, you catch people that are lifting things off of the aircraft. Today’s miniatures are tomorrow’s full bottles.
The reason for allowing crew to purchase stock has to do with customs regulations. Most countries it is illegal to remove aircraft stores from international aircraft as they are “bonded”, ie tax free.
However when they are purchased even at a nominal rate, they go from being aircraft stores to personal property and can be removed. The crew will have a receipt of payment.
Most countries it is illegal for passengers and crew to remove catering from international flights. The left over catering is normally incinerated due to quarantine requirements.
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