My Dad had a book of voucher tickets for GLA-LHR in 1980’s and anyone could use them, noone bothered about what name was on it. Me and my sister often just took one under his name. and some scribbling at check in.
In those days everyone had to ‘check in’ BA at GLA had about 8 desks, a help desk and a separate Reservations centre.
Think there was a BAC-111 on standby for the Shuttle guarantee.