Frozen drink dispensers are a common fixture in convenience stores around the country. They are used to store and serve premade smoothies or slushies. These units have built-in agitators that gently mix the drink all day long. The constant churning keeps ice chunks from forming and add a little bit of showiness to entice customers. There are a lot of different designs of frozen drink dispensers available. Some have see-through reservoirs and vibrant colors to create the aforementioned showiness.