In the UK most towns have at-least 2 large supermarkets in the town, and within 20 minute cycle-drive at-least another 3.

In the UK, there is choice between: Asda, Tesco, Morrissons, Aldi, Lidl, Sainsbury's, Waitrose, M&S

Who competes with Amazon? (Ebay?)

The fundamental problem with Amazon is as with Standard Oil when they bought the railway companies. Amazon marketplace & Amazon warehouse/delivery/logistics should not be one company.

There is a massive opportunity for a new marketplace to compete with Amazon; because Amazon has very little trust amongst both buyers and sellers alike - but where else is there?