buy at vs sponsor

buy at is not a noun while sponsor is a noun.

Word	Noun	Adjective	Verb	Adverb
buy at	No	No	Yes	No
sponsor	Yes	No	Yes	No

As verbs, buy at and sponsor are synonyms defined as:

buy at and sponsor: do one's shopping at; do business with; be a customer or client of

Other synonyms of buy at include frequent, patronise, patronize, shop, shop at.

buy at (noun)	sponsor (noun)
	someone who supports or champions something
	an advocate who presents a person (as for an award or a degree or an introduction etc.)

buy at (verb)	sponsor (verb)
do one's shopping at; do business with; be a customer or client of	assume sponsorship of
	assume responsibility for or leadership of
	do one's shopping at; do business with; be a customer or client of