I do not have a car because I cannot afford one. Social Security is not that generous! In my town not having a car is a real drawback. The bus service here is less than great. Buses run once an hour and do not go everywhere. BUT I can take my mobility scooter on the buses at least. If I could afford a car, I could afford taxis/uber.
The cost between having a car with insurance, repairs, gas, oil changes, registration, etc is not near the same as taking a taxi or Uber. And Uber is easily half what a taxi is and cleaner and quicker. The bus is cheapest but not always convenient. We have a free dash bus that goes in a circle around our downtown area.
Bartering with friends, neighbors, and family for rides is another option.
Also, there are mobility transports for the disabled or wheelchair riders to regular community events or shopping. (just google it) I know that some ambulance companies offer non-emergency transportation for scooters/disabled. I found the rates reasonable if booked in advance, but it is not required. And both these modes of transport had loyalty plans you could join to save even more money. With or without a guest rider or your chair/scooter.
Also, we utilize a home health aide that Medicare &/or Medicaid pays for depending on your disability. I personally do the transport for Dr appts, the grocery store, or other errands while bringing their chair in my vehicle. I will usually call ahead to see about wheelchairs or scooters at the destination before I transport the chairs.