Apple Tree's at the very least should be treated as containers that hold 5/5 apples per tree with the tree regenerating about 1 apple every 30-40mins?
At the moment, farming apples forces you to sit in the same spot and highly discourages exploration and movement. By making them a container, the player would be forced to search around the towns for any available apple trees to pick
Along the way, he/she would be able to search through houses as they search for trees, increasing their reward rate as they go.
Towns with large apple farms would be seen as high priority areas, possibly attracting other players to fight over the apples?