Because of the golden rule, "do unto others as you would have others do unto you". In other words, you get what you give.
It depends on the practice you are employeed by. Each employer names his own pay rate and benefits package.
With an MSW you can work with the Department of Children and Family Services as a social worker working in Child Protective Services, Child Welfare Services, Family Reconcialiation Services, a hospital as a clinical social worker, Department of Corrections
It takes 6 years to get a Doctor of Pharmacy degree and then you have to pass a state board exam.
If you have a Bachelor of Science, some schools cut that down to 4 years.
Private practice, pediatric clinic, or hospital.