You provided your address and they still invited you as a tack-on to your daughter's invitation?
No, that's rude. However ... as you pointed out, your sister and niece are not the one who issued the invitation, so even though it was "off" I wouldn't let it deter you from doing what you want to do. If you want to attend, go and enjoy the festivities. If you don't, just RSVP in the negative.
It may be that they're quite young and inexperienced in how these things are supposed to be done. So even though someone messed up by not sending you your very own invitation you should show them what 'class' looks like by sending an RSVP, either way.