Why are people so scared of? ...?

I was just watching something about loan sharks. And I cannot understand why people are so frightened of them. I mean, everyone knows someone a lot tougher and more capable. For example, how does a loan shark know he's not lending to a soldier, police officer or even a career criminal with a large firm. It's another part of a culture in this country of people being scared of the wrong people. People in track suits, gangs of teenagers, lads in pimped up s*it cars. Bring back proper firms eh?