We can’t expect non-Jews to live by OUR ideals.
We CAN expect them not to offend our sensibilities in our neighborhoods. Yes, I know, we don’t own the neighborhood, but it’s downright obnoxious to put up such signs in a neighborhood with a high concentration of religious Jews.
They deserve absolutely no sympathy.
And let’s face it, they know it’s immoral as well. Only a few years ago, these types of signs were unacceptable even for non-Jews. The unfortunate decay in societal morals does not change the intrinsic immorality.