7% of US households don't have a bank account.[1] Many people live in walkable areas, carpool, or rely on transit. Visiting a doctor doesn't require ID. Taking a train or plane (or a bus) is easier with ID but possible without.
Regulations for dispensing controlled substances vary from state to state. As of 2013, only 24 states required pharmacists to verify identity.[1] Many of those regulations apply only in certain circumstances, don't specifically require government-issued photo ID, have fallback procedures, or allow the pharmacist to dispense the medication without ID if withholding it would harm the patient. Florida recently passed a law that says it's good enough if the pharmacist recognizes the patient.[2]
[1] https://www.cdc.gov/phlp/docs/menu-pdil.pdf
[2] https://www.healthlawrx.com/2018/07/florida-imposes-new-id-r...