Many rural areas in Ausralia have small scale local area market gardens, here in W.Australia most everything I eat is sourced within a 15 - 20 km radius be it flour, olive oil, lambs, oranges, etc (even the odd banana and a fw mangos) - but that's a far cry from the dedicated single crop volumes required to supply cities and for export.
Worldwide there's an issue with regions being devoted to mainly a single crop intended to supply tens of millions across several cities, often overseas.
Good when it works, better have a backup alternative when that fails.