As the sentence "This store stores a large store of rubber ducks" will tell you, store is a word with a lot of definitions. Among these are "a place that sells items," "the act of keeping things for future use," and "a supply of something."
As a noun, store often refers to a place where things are sold, such as an electronics store. This meaning of the word likely sprang up from the original meaning, "a supply of something kept for future use." As a verb, store refers to the act of putting things away for later. Chipmunks store nuts in their cheeks, people store their winter clothes when springtime arrives, and techies store information on backup drives.