In the world of fast food, I see this as a problem. Taco Bell released the Dorito Loco Taco which has now made its way on to the main menu. Subway releases new promotional subs and items like the Flatizza, it seems almost bi-monthly. While the latter may not be as big of a success, it still garners awareness.
I can't think of one "crazy" item Burger King has released in the last few years.
Inventing something is "easy"
Now, after inventing it you have to:
- engage your whole supply chain for the needed ingredients and make sure they reach their destination
- engage marketing, produce all the needed support (packaging, new menus, new billing items, etc)
- create procedures and train staff
- deploy new equipment if needed
I mean, it's mexican food, for breakfast (not!).
So ya, nobody does do "crazy" anymore in Fast Food. Just normal, add some more onions + BBQ Sauce and it will sell.