Best Supermarket in Corfu Κέρκυρα Gouvia-Sklavenitis 

There are plenty of supermarket in Corfu, you do not have to worry , once you are out from the Airport there is a big size Liddle with very cheap products, we bought all our essential here, it is 2 minutes from the Airport by Car.About 15 if you are walking as I do not know any local road.
There is Also Sklavenitis in Gouvia which is 5m about 3 miles from the Airport and you can reach it within 10-15 minutes as there is no traffic .