I take an amazing photo and give it to you with all rights to redistribute and sublicense it as you wish. You choose to redistribute it under a restrictive license for cash. As far as you know you're the only person selling this photo.
You see my photo being used in a national advert. The advertiser is not your customer. Again, you think you're the only person with the right to redistribute this photo, and infer that your rights to a licensing fee is being infringed.
As I say, they were stupid to treat this as if they had an exclusive license, but they had every right to redistribute under their license and ask for a license fee. Just as the recipient of that demand had the right to tell them go away.
You see my photo being used in a national advert. The advertiser is not your customer. Again, you think you're the only person with the right to redistribute this photo, and infer that your rights to a licensing fee is being infringed.
As I say, they were stupid to treat this as if they had an exclusive license, but they had every right to redistribute under their license and ask for a license fee. Just as the recipient of that demand had the right to tell them go away.