Gosh, I have never come across having the birthday guests paying the entry. I just think she has set her sights on this fantastic place that she wants to hold her kids party no matter what but it is way out of her budget and now all the guests have to wear it. Half the time I would just rock up without any money to drop DD off to a party, which I am sure alot of the other parents will do if it isn't stated on the invitationl. Very rude IMHO.