WOW that sounds awfully strict of Disney - I presume anyone can make a consume a cake, but it's the sharing of the image or profiting from it that's illegal?
There is a body of law that is referred to as “fair use.” Most people misunderstand these rules; they believe as long as they give credit to the author/designer/creator then they’re not in violation of patent law. But that’s not the case. There’s only a couple of conditions in which fair use is valid. Movie characters usually fall under trademark. There’s only a couple instances in which an individual can use a trademark without permission. When you reproduce trademark protected work and put it out there as your own work you are violating trademark law.
On the face of it it does seem quite harsh. But it’s driven in part by the cost to companies to secure their rights to their intellectual property, designs, inventions, original works, etc.
I used to work for one of the largest law firm’s in Washington DC, in the patent law department. Large companies spend millions of dollars to obtain patents, trademark, copyright. For companies that do international business they not only have to protect their rights within the United States, but in every country they do business. There’s networks of attorneys in every country to complete the necessary research and paperwork to obtain those international rights.
Once a patent, trademark, or copyright is granted, registration has to be renewed, sometimes annually. I could spend several weeks on a single renewal.
Companies make their money through licensing agreements. Counterfeiting doesn’t just take away from their profit, but it also encourages counterfeiting. Disney knows the little cottage food operator is not going to cause them to go broke. But if they turn a blind eye to the small business or to hobbyist taking advantage of their intellectual property, then it emboldens more companies and larger companies to do the same.
For the companies who pay for license agreements, which are not cheap, it dilutes the value of those agreement. So when Disney, Lucas films, and Sanrio joined forces, it was also meant to send a message to their license holders that they have their backs.
I won’t make a cake with any trademark characters. I’ll buy toppers or character figurines to put them on the cake. That way it’s all legal, plus the child gets to keep the toy after eating the cake.