The Eon Ticket in Emerald is a special case
Besides that there are two different kinds of event distributions: Mystery Gift, which has wondercards and didn't exist in RS, and Mystery Event which already existed in RS but didn't have wondercards.
In both cases there's a script downloaded into the save file. It's just that the Mystery Gifts are always bound to the postman in the Pokemon Center while the Mystery Events could be bound to any NPC, not only Norman.