I used to make that drive a lot. Once in the late 1970s when I was maybe 19 I picked up a guy hitchhiking right where I-75 went past Gainesville. I'd driven down there on a whim to see a girl and didn't look forward to driving back alone. This guy was probably early 40s, but seemed ancient to me.
He had two huge suitcases. From the looks of him, the material goods he'd accumulated in a lifetime were contained inside them. We started talking, and he told stories about living more or less as a hobo working odd jobs through the south as we drove through the night, through north Florida, up past Valdosta and Macon. He fell asleep near Atlanta and stayed out until we hit Tennessee. I was staying awake popping NoDoz or maybe something stronger. He'd told me he was getting out at Knoxville, so I woke him in time. He thanked me and was on his way.
I was nearly to Lexington before it hit me -- those two suitcases were still in the back.
I drove all the way back to Knoxville just in case he was hanging around where I dropped him off, but of course he was long gone. I looked through the stuff in case there was something really valuable, but it was mostly just old clothes. I couldn't think of anything else to do, so I left the suitcases concealed from the road but where you could see them in you walked by. But I know he never came back for them. I still feel a little bad about it.