Why do so many jobs require that you have at least a year or more degree in a field to apply for that job?

Why can't an entry level person find a great job that pays well as if you have a degree? And why odes the employer tell you that you are not what they are looking for because you are not qualified and you ask them hwo do yo ubecome qualified with out havign to go to college, because most people cant afford it or are unable to get grants or help to go to college. So how can I find a job that pays well as if i have a degree without having to go to college and then never end up use my degree.