Weird news: Owner of horse in prize picture demands share

Sometimes a news item can seem funny, but wherever there is some money involved, it is also serious. The concept of copyright / model / property release is a hot reference in the case of stock photography, with disputes ongoing all the time. However, at the same time, there are many clear trends in terms of actual laws - the concept of what requires permission, and what does not require is settled to a large extent.
The issue here is interesting. On a public path, a photo was taken which also included a horse (with a unique type of smile and open mouth); this photo was submitted for a prize and won the prize. At this, the owner of the horse demanded a share in the prize. The prize was in terms of a holiday, and a holiday cannot be shared anyhow, and the prize recipient rejected the demand. Legal opinion dismissed this demand (link to article):

The owner of a horse that photobombed a selfie taken by a father and son has demanded a share of a prize worth £2,000 that they won after entering the image into a competition. David Bellis, 31, said his three-year-old son, Jacob, took the photo as they were out walking near their home in Prestatyn, north Wales, and they entered the picture into Thomson Holidays’ Made Me Smile competition. After they scooped the main prize, a £2,000 holiday, the horse’s owner, Nicola Mitchell, contacted Thomson Holidays to complain, claiming Bellis should have asked for consent. Bellis said: “I don’t understand why Nicola is so annoyed. I was on a public path that everyone uses to go to the local school and everyone sees the horse there.”