Nobody likes a gatecrasher.
If I were organizing a party, I wouldn’t want anyone who’s not on my guest list to come barging into my party to mingle with the rest of my crowd. And if someone else were throwing a party in my honor, I’d probably feel pretty much the same way . I mean, it’s supposed to be my party, right? So I should be able to choose who gets to join it and who doesn’t. So you see, I wouldn’t exactly be thrilled if a bunch of uninvited and unwelcome guests suddenly showed up at the door—unless maybe they brought pizza, of course!