I'm not complaining, cause I love my Mario/Banksy crossover t-shirt, but it's just how it is, Disney & co just don't bother going after them, they're happy to sell you their official™ stuff through other channels.
If you hire someone to print it on the shirt for you, and then distribute the shirt, you would be liable for copyright infringement, not the printer, because the printer isn't supplying the artwork, you are. It's no different than placing phone calls to perform an illegal activity. The phone provider isn't guilty, but you are.
If you order a custom shirt, and provide unlicensed copyrighted artwork, but don't distribute it, then no one is in a position to get in trouble.
That is just not true. A copyright gives the owner thereof exclusive rights to make a copy of his work. Neither the creator nor the copier have to sell anything.
https://www.law.cornell.edu/uscode/text/17/106
Noncommercial use is a factor to be considered for fair use if the copier is doing it for a protected purpose. (Creating a t-shirt for your personal use is not a protected purpose and can therefore never be fair use on its own though.)
The reason someone making a personal shirt doesn't get sued is because suing people is expensive, that harms goodwill, and Disney isn't getting any money from such a person anyway.
So I assume that a lot of self-publishing type companies may refuse to do copyrighted stuff, even for one-off jobs.
But it's entirely possible that I'm crazy, anyway. You're probably quite perceptive.
So torrenting movies is legal?
There was a cool design (or at least I thought so) I came up with. Had about 100 of those printed.
Went to Amazon to get a seller account:
1) learned that if I had only 1 tee-shirt with a single design to sell, I couldn't get the account.
2) after researching the competition, discovered that many of the tee-shirt designs for sale were:
Boggled my mind that Amazon was okay with this.