A label usually contains information about contents or a product. They usually have three layers: Printing, adhesive (glue) and lining, which can be removed. Other times they are just coated and applied, as with soup cans. A sticker always comes in the form of design, adhesive and lining, as mention above. They do not necessarily contain any information as with a label - the front may often only contain some design.

A label does not necessarily stick. So sticker is a kind of label. Yeah, it sticks.