I've had that problem too, but not to the degree of some of you. I'm a pretty sarcastic person so all I say in reply is "Hey, if you happen to be taking a Mexico vacation at the same time as I get married I can't do anything about that." I haven't had to, as of yet, actually uninvite anyone that has invited themselves.
On another note, I am booking Claudia Rodriguez for my photos and was wondering if anyone has had good or bad experiences with her? So far the communication process is slow going, I'm still waiting for her to send me the link so that I can put our deposit down!!