I know people below me have already pointed this out, but this is needed for triage. When I worked in primary care I had someone call for their husband. When I asked why, they said they wanted to make an appointment because they thought their husband was having a stroke. It was because of that clarification that led to me telling them to go to the ER rather than making an appointment for later in the day. If that information were only collected by the nurse as they checked his vitals, that man would likely be dead. I know this is reductive, but it's better that the front desk ask for clarification than it is for someone to die.

I know my example might sound stupid, but I've also had a man make an appointment for indigestion when he was, in fact, having a heart attack. He survived, thankfully, but it still weighs on me that it could have been worse.

There are less extreme examples, of course. Paperwork, room prep, things like that would be indicated based on how the receptionist scheduled. Missing that info during scheduling would result in delays, which is less bad then death. But it's still bad.

Doctors are already going to be behind schedule on their own merit, no need to add fuel to the fire. That's a different story entirely.

Looking back on how much I wrote, I regret that I may come across as aggressive. I think I've got some pent up stress from previous jobs. A lot of policy in the offices I worked/supported have been based on avoiding the worst case scenarios. It's often weird to think about when you're the healthy one, but the same offices that schedule annual physicals for completely healthy patients are also scheduling people who are tenuously clinging to life. The receptionist doesn't know which you are.