‘Your mother can’t produce food out of thin air,’ said Hermione. ‘No one can. Food is the first of the five Principal Exceptions to Gamp’s Law of Elemental Transfigur—’
‘Oh, speak English, can’t you?’ Ron said, prising a fishbone out from between his teeth.
‘It’s impossible to make good food out of nothing! You can Summon it if you know where it is, you can transform it, you can increase the quantity if you’ve already got some –’

- Deathly Hallows, Chapter 15

From this, we can presume that food production is one aspect of wizarding society which can't be completely magicked away. The benefits of the division of labour suggests that farming is a wizarding occupation, unless they rely exclusively on trading with muggle farmers.