Is this acceptable behaviour? There will be 30 kids. I don't want people to have to bring anything/wrap stuff/spend money. Also, more selfishly, I also don't want to have to remember who got what. DD is 5.
P.S. Before the "THIS THREAD HAS BEEN DONE BEFORE" brigade leap in, yes, I'm sure it has. Just want your live, up-to-date opinions please. 
Many thanks.