To me it is just rude.
I recently had a somewhat similar experience,... A few years ago I had a Christmas party and invited a few friends/ neighbors and a few co-workers. Once I issued the invitations, I had 2 different CW ask if I was inviting So and so. I replied no and was asked why? don't you like her??? I liked her fine and no she is not invited.
Another former CW/friend ask if she could bring a friend. CW didn't drive at night but really wanted to come so I relented. We ended up with a guest list/ sit down dinner for 12.
2nd year I decided to once again have the party. Guest list was almost exactly the same except for CW and her driver. One of the guests from the previous year accepted the invitation and showed up at the appointed time with a guest of her own in tow
.( this being someone who had been the year before and saw our set up and our space limitations as well as it being a sitdown dinner.) Also CW who asked about issuing invitation to so and so... she told a different CW on year 2 who apparently really wanted to come... is so dissapointed... can she come too???..... no!
Years 3 and 4 I only invited a couple neighbors so there were only 6 of and and it was lovely!
This year, I don't know what got into me to think it would be any different but I wanted to have the slightly larger party again, so I mentioned to 3 of my CWs that I was THINKING about it .
Within 4 days one CW had already invited a guest of her own and another had asked was I going to invite other former CW .I told her no, hadn't planned to. " Oh, really, I thought since you had worked with her once before..." She asked about 4 different ways , I told her not really, but I'll think about it. I called her back a few days later and told her not invite her... you have been to my house twice before for this party and you know our space. Her reply... " well, I thought you meant to anyway so I already did" at which point I reminded her that I never said I actually was giving the party... merely thinking about it, so she had best call her back and recant her invitation.
Next day I got a call from my CW who said she probably couldn't come anyway and since she couldn't another CW ( the one who previously brought her own guest) wasn't either. I told her OK we'll miss you both.
It just feels like they want to use my house as a venue with free food so they can hang out with the people they want to rather than come see me. And thats hurtful.
Then I proceeded to plan my redeuced size party with just the neighbors and look forward to a wonderful time. It's next Sun evening and I can't wait
Having said all that, I am firmly in the camp of it is just plain rude to put the hostess on the spot, and then not to accept no for an answer but to keep on asking until you get the desired answer.