Yeah a red light would flash over the booth and the door would shut closed, hence having to put your foot in there. Alot of people buying and using these cards were like 'bullshit!' but this guy who told me about this figured to err on the side of caution anyways and ended up having to comically escape the situation with all these people looking at him.
This was like 5 years before my own time in Japan but pretty hilarious nonetheless
I'm not saying you're wrong but a) this sounds like a massive safety issue and b) this sounds like exactly the sort of thing I'd say to anyone trying to get a dodgy phone card from me, "yeah you need to wedge your foot in the door in case it detects the card is hooky, and tries to lock you in" just so I could stand there and laugh at their contortions trying to keep one foot outside while they use the phone.
Heh yeah I feel the same but the 90s were a different time
Remember playgrounds back then? I remember one around Osaka Castle which was like a huge children's slide with those industrial conveyor rollers you rode down on pieces of cardboard (to go stupidly fast!),which I'm sure you could pinch yourself on really bad.
This was like 5 years before my own time in Japan but pretty hilarious nonetheless