A national TV network has a series with a funny recurrent trope: a model pig that lets out obnoxious noises. The problem is that the pig was a real product and the product maker had not given permission to feature this unique character. A lawsuit was filed and recently settled. How does a production company, YouTube star or network protect itself?
Through the clearance process. Clearance lawyers vet a show through the script and through rough cuts to determine if there is liability exposure. They keep an eye out for unsanctioned use of products, photos of real people that are not originally in the shoot (i.e. someone hung them to be featured) and disparagingly mentioning real people.
While a number of these can be defended on fair use grounds, who wants a lawsuit? I defended a well-known case years ago and was searching for an expert. I called a highly credentialed professor who answered my inquiry this way, “ Jeff, I am of two views. One is that this is defensible as fair use; the other is, be a mensch and get a license!” Being careful is always a good idea.