Concept: Instead of needing to drink water or cook for yourself food in order to satisfy thirst and hunger, artists can perform selected tricks in order to accomplish that.
Example:
Instead of drinking water, the juggler would have to juggle with 3 balls for 15 seconds. And he would not be thirsty anymore.
Instead of eating breakfast, the magician would have to perform a 10 minute routine.
If one wants something sweet, thy will have to perform something that gives him this taste.
Further Developing the Concept:
One can only know what a respective sleight tastes like only after having performed it.
Depending on how well you perform your routine - your "food" tastes differently.
If you fail an effect/sleight/routine, what you taste is foul/rotten food.
Sketch Template
We are being walked through a community of homeless people. These are seen to perform little effects (like vanishes, cuts, color changes, bouquet appearances) in order to satisfy their vices, hunger or thirst. The camera stops on two homeless guys. One asks the other if he would like some rum. "Rum? Where's you learn that?" asks the other. "A boy gave me a tip the other day and I kept practicing it. It tastes pretty good. Here, I'll teach you." This could be an opportunity for a tutorial inside the sketch, or you could just fade in fade out to the second homeless performing what he has been taught. "Damn. It's strong." The camera switches its focus towards the street, where we see normal individuals minding about their day. On the other side of the street, a mirror reflects the image of our two protagonists. "You one ugly bastard." says the first. After a short pause, the second replies, " It's just the rum, but thanks."