You say "It's rude to not play by our rules". They say "It's rude of
you to expect us to change our business model to support your niche
market differently from the way we support everyone else." Neither is
wrong...
Honestly, I think it *is* wrong to sell someone a physical product and then
not tell them how to make it work. If you're not actually selling them the
physical product but selling them a way to get a particular thing done, then
don't represent that you're selling them physical product because that would
presumably include the right to use it any way they wanted provided it was
lawful.
How would you feel if you bought a car and then discovered that the
manufacturer had welded the hood shut? How many people still do their own
oil changes anyway?