The main reason I buy local fruits is because of quality. If you have to ship fruits from another country they're usually frozen and far too ripe when picked. On the other hand, when fruits are made for local consumers they are picked at the right amount of ripeness and aren't frozen. I can hardly eat a peach at a large grocery store nowadays simply because of the difference in taste.
Tomatoes are a great example of this. Because they have to be shipped, commercial tomatoes are picked before they're ripe and then gassed with ethylene to make them turn red. As a result, home-grown and locally grown tomatoes tend to taste noticeably better than typical store-bought ones since they're properly ripened.
