I have a huge problem with that. I also have a problem with people expecting you to change your plans to accommodate them. I just refuse to do it anymore. If I were you I would tell the person/people when they come over "I'm sorry, we were just on our way out. I'll call you later OK?" That way you're rid of them, and maybe they'll get the hint without you having to come out and call them on coming over unannounced and uninvited. Hope this helps...