Per this thread "Mr. Pibb + Red Vines = Crazy delicious"
I did wonder why they were so “crazy delicious”, now I see that it was all part of the surreptitious plan to sneak food into the theatre, and that you could use a “Red Vines” hollow whip candy as a flexible stealth straw to drink your Mr. Pibb unnoticed by theatre security.
Ah so!