I don't know that "oblivious" is the word I'd use. People standing next to the racetrack are well aware of the risks involved. They aren't there because they don't perceive the risk; they're there because they think it's worth it.

Would you describe rock climbers as "oblivious to the risks involved", or just as people who are sometimes killed by their hobby?

Cars, perhaps.

For another recent historical example see: smoking.

Personally I'm waiting for when sitting at the desk all day long is found out to be Very Bad. But that's probably just a modern ‘proletariat vs capitalist’ issue—I guess factory assembly lines weren't and aren't too popular either.