Very common misconception. There is no law in the US that says that you're not allowed to make money off of other people's stuff, and there are plenty of rights

Very common misconception. There is no law in the US that says that you're not allowed to make money off of other people's stuff, and there are plenty of rights in the US that as a side-effect happen to protect your ability to make money off of other people's stuff. Some of those rights are even embedded within copyright law. Parody allows you to make money off of other people's stuff without their permission. I really object to the phrasing of copyright law as "you don't have a right to make money off of other people." That's turning copyright law into something much, much broader than it actually is. I get that this might seem like a trivial or nitpicky distinction, but if you're familiar with Doctorow's writings around concepts like "felony contempt of business model", there is (I believe) an uncoordinated but persistent effort towards rephrasing copyright as if its purpose is to enshrine some fundamental right for a business to make money and to control who can make money around them. And it's a really insidious expansion of what copyright actually protects. If people aren't violating an actual copyright (which, we can debate if lets plays do), they are in fact allowed to make money off of your stuff, and the fact that your stuff enabled them to make money does not automatically obligate them to compensate you. Not everything that allows someone to profit off of another person's business is a copyright violation.