shopkeeper vs market keeper

shopkeeper and market keeper both are nouns.

Word	Noun	Adjective	Verb	Adverb
shopkeeper	Yes	No	No	No
market keeper	Yes	No	No	No

As nouns, shopkeeper and market keeper are synonyms defined as:

Other synonyms of shopkeeper include storekeeper, tradesman.

shopkeeper (noun)	market keeper (noun)
a merchant who owns or manages a shop	a merchant who owns or manages a shop