#StealMyIdea for 2 reasons...
First, we need something to eat on the way home. We buy fast food because we're hungry, and we don't want to wait to sit down and eat at a restaurant or cook something at our house. If you added an 'Appetizers Menu' filled with easy to eat finger foods, that come in a cup and easily fit in our cup holders, we could grab something quick for the trek home without messing up our shirts.
Second, appetizers will upsell everyone. The dollar menu was an innovation that forced us all to add a few extra items to our order. The 'Appetizers Menu' will continue this trend.
In conclusion, this idea is more about standards than food in a cup. I have seen a variation of this idea before, but adding a new menu called "Appetizers" will change the game for everyone.