I didn't tape any gameshow moments, but with regular TV Shows, I used to tape over all the time.
These where the days when I still had a mono VCR, didn't have a drivers liscence to easilly go out and get new tapes, or a paying income to easilly get tapes, so I had to pick and choose what I wanted to keep. I have a few tapes where I started to tape something over one show, decided I didn't need it, and stopped. Another where I taped the first 5 minutes of it, decided I didn't need it, and stopped...
Years later, of course, when I become a better organizer of the shows I tape, this made it increasingly annoying to organize all these shows, as they where scattered across many a different tape. It wasn't untill 1993 that I started organizing things better.