Rant: Rude People

I just have to rant about some super rude people! We are a still (a week out) having guests tell us "well we aren't for sure if we can come or not, we might just show up" to which my inner bitch wants to respond "don't bother" or "come and I will have a sign that says "standing room only for those too rude to RSVP with the self address and stamped card" but instead I repeat "we had to turn in our numbers weeks ago and will not be able to add anyone last minute" to which they still respond "it'll be fine we might just show up". And then there is the matter of people texting us saying, "Is it okay if we bring X,Y,Z with us?" when X,Y,Z were never invited. Like I get it, I had a bridesmaid whose FH could not come with her and she was coming from out of state so she is bringing her mom, I am fine with that. These people are wanting to add like 3-4 people that we don't know and don't have room for. And FH says he feels rude saying no. I feel like they are rude for asking! UGH!!