The first time I tried a public charger I sat in the car to see what happened. It charged just fine. Then later, on a long journey, I left the car on a rapid charger and went into a shop. When I came back I put my purchases in the boot, then opened the car and got into the driving seat. The radio came on, and it was playing something I really liked. So I sat there listening to it, watching the SoC continue to rise on the car's screens, then at about 95% when the music stopped I got out, stopped the charge, and continued on my way. None of this interfered with the charging in the slightest.
The only time it ever stopped while it was charging was when it was on the granny lead in the garage. I went out to get my camera from the car, and when I opened the door the charging stopped. I had to begin the charge all over again. Don't know what was going on that time.