Yes, and that's why Postel's law is more of an empirical observation (a law of nature, if you will) on which software survives and which doesn't. You may dislike it but that won't make it go away.

I see it as the opposite, actually. They will pay you for a robust product: one that works for them. They have no care for the technical minutiae of your implementation, because they're just trying to do actually interesting things, with the help of your product. This is the customer perspective.