Found Horse

At the intersection by my house there is a sign on a pole that says "Found Horse" and then a phone number. Why this makes me laugh everytime I see it I'm not sure. Maybe it's because most residential areas don't have a lot of horses. Or maybe it's because I get a lot of animals in my back yard (I don't have a fence) and I picture waking up one morning, opening my blinds, and seeing a horse grazing on my grass.