If you buy a hammer and get mad that it doesn't make pizzas, the merchant isn't going to accept that, nor is a judge in small claims court going to be remotely amused. It's a hammer. Stop wasting my time, plaintiff pays all court fees and time for the defendant. They deal with bullshitters all day and they generally tend to be completely unamused by it.
If you ask the merchant nicely they will probably take it back, most retailers have return policies and most of them will stretch them even further to keep the business of a repeat customer. But merchantability is a thing, and they can't sell you a thing labeled as a hammer that doesn't work in the way an ordinary reasonable person would expect a hammer to work. One person being an unreasonable person doesn't really change that.
If you try and abuse it then the judge is gonna slap you down, but if they try and fuck you around about how a toaster is kind of a hammer in some ways then the judge is gonna slap them down.
These two aren't the same thing. That the hammer works as most expect a hammer to work isn't the same as that the hammer works as I expect it to work. If I try to take my hammer back because I thought hammers also worked on screws, I'm pretty sure they aren't obligated to take it back. It would be very hard to argue that your new RED camera isn't "fit for purpose" due to its onerous EULA, because plenty of people successfully make films with RED cameras.