GB Airways is not BA, commercially or financially. Actually, the food is normally better than BA, especially in CE, and as previous pointed out, its champagne from a regular bottle. They never serve birdseed as far as I can see. As a franchise, they follow branding but are free to set their own prices, headsets included.

US airlines (AA, CO, etc) charge for headsets in economy on domestic flights but they are free in FIRST. AA and CO are definitely full service airlines.

Give me GB Airways over BA european flights any day. Bummer that they are being bought by Eastjet.