If nobody pays for it, there will be no product.
That's how it would work if all creators did what I'm suggesting they should do (i.e. crowdfunding every project and not doing the project if they don't get paid enough money for it to be worth their time). The way most creators do it now, the creators create the product for free and then if nobody pays for the product (regardless of whether or not they acquired it through other means), they just spent a lot of time and got nothing in return but the product definitely exists.
if everyone is a utilitarian who thinks the way that you do, why does anybody have to pay for anything?
I don't think there exists a utilitarian who thins the way that I do. I'm not a utilitarian, I'm an ethical egoist (which is why I download stuff for free and then don't donate to charities outside of special occasions when I happen to feel like donating money either to a creator I like or a charity I like). People have to pay for certain stuff that has value (like services and physical items) because that stuff is limited and not freely available to everyone.