Pokemon Squirtle travel BPA free plastic cup with screw lid and straw. "A carnival cup is a cup made out of plastic. It is most commonly used as a container to hold beverages. Some are reusable while others are intended for a single use followed by recycling or disposal. Carnival cups are often used for gatherings where it would be inconvenient to wash dishes afterward, due to factors such as location or number of guests. Plastic cups can be used for storing most liquids, but hot liquids may melt or warp the material.