Frankly they had a great deal mostly because it was easier for tfl to say you give us £x (which was a small percentage of what the advertising revenue could have been) so we don't need to find a million advertisers each year and so they had a confirmed source of revenue for the beginning when no one really knew if it would take off.
Tfl (or more likely an ad agency) will make a bucketload of cash when Barclays stop being sponsor.
Frankly they had a great deal mostly because it was easier for tfl to say you give us £x (which was a small percentage of what the advertising revenue could have been) so we don't need to find a million advertisers each year and so they had a confirmed source of revenue for the beginning when no one really knew if it would take off.
Tfl (or more likely an ad agency) will make a bucketload of cash when Barclays stop being sponsor.