They don't have to give people schedules, that's not part of the status "worker". In fact, if they did, the drivers would likely be classed as employees instead

They don't have to give people schedules, that's not part of the status "worker". In fact, if they did, the drivers would likely be classed as employees instead. You can be a worker, turn down work whenever you want and work for multiple companies. That's all fine.