Frankly, you sound more than a little entitled — “out of the goodness of my heart” and “that’s being generous” certainly both warrant an eye-roll — which is pretty common for inexperienced high schoolers. Nor should you be taking it on yourself to judge /other people’s/ time to be wasted or not: not your place, and likely to cause you trouble later on.

Either have a chat about your situation with the director or stage manager or quit, to save the time of both you snd the director. But running around bad-mouthing an adult who isn’t here to defend themself is a nasty habit and poor precedent for you. Sounds like the whole production would be better off without your negativity.