The problem is that you're thinking in absolutes. That's not how life works. The driver doean't need to be a formal part of the hiring process that everyone rigorously goes through. There's variation and difference for every candidate. That's just because hiring is a human process.
In this case just knowing the driver well enough to ask them "Was that person nice to you?" when they drop a candidate off gets you another very useful signal when the response isn't neutral. A lot of the time it'll be "they were OK", but occasionally you'll get a positive "they treated me like a human being" or a negative "no, they were rude".
If you just get an "OK" then you're back to hiring as normal, without the extra data. If you get a positive or negative signal that can amplify what you see in the rest of the hiring process. For me, a tick in the "nice to people you don't have to be nice to" box is a good thing. I like to work with people who have that trait. If I can find a signal that indicates a person has it then I'm going to use it when I'm hiring.
In this case just knowing the driver well enough to ask them "Was that person nice to you?" when they drop a candidate off gets you another very useful signal when the response isn't neutral. A lot of the time it'll be "they were OK", but occasionally you'll get a positive "they treated me like a human being" or a negative "no, they were rude".
If you just get an "OK" then you're back to hiring as normal, without the extra data. If you get a positive or negative signal that can amplify what you see in the rest of the hiring process. For me, a tick in the "nice to people you don't have to be nice to" box is a good thing. I like to work with people who have that trait. If I can find a signal that indicates a person has it then I'm going to use it when I'm hiring.