I am an attorney who deals with medical offices and patient issues commonly. No, this is not standard practice. There are some offices (Id say under 5%) trying to foist this nonsense on their patients. It usually happens in really huge institutions like major cancer centers or university-related systems of medical clinics. But even some smaller clinics have tried it. Its all in the name of efficiency, which it definitely is NOT.
Ill give you the same advice I give my clients (and which I followed myself for the brief period when one of my doctors offices tried it): say no. Even if that time and date is ok, say no and make them reschedule it to YOUR preference. In your case, call them and confirm, as well. When they discover the number of immediate and later constant reschedules they have to do, most clinics that try this go back to normal scheduling. I know mine did, within about 2 months of starting this dumb experiment.
Youre not old and cranky. You are not a number to be processed, but a living, breathing patient with specific human needs. Have no doubts, and make no apologies, when standing up for your own medical care. Taking care of YOU is their business; you arent there as an inconvenient but necessary resource for them to make money.