Adding new benefit payment days lets Social Security give better service to you and other beneficiaries, workers and other members of the public. It's an important question. Medicare is an insurance program. Medical bills are paid from trust funds which those covered have paid into. It serves people over 65 primarily, whatever their income, and serves younger disabled people and dialysis patients.
Patients pay part of costs through deductibles for hospital and other costs.
Small monthly premiums are required for non-hospital coverage. Medicare is a federally run program. Medical bills are paid from federal, state and local tax funds. It serves low-income people of every age. Patients usually pay no part of costs for covered medical expenses.