Why So Harsh?

UK television commercials are so harsh. The latest advertisement to premiere on the tube is one for car tax evaders. As the announcer states, "If you don't pay your car tax, we have the legal power to clamp, tow or even CRUSH your car." It's just one of many advertisements that scare people into doing or not doing something in the UK. Why so harsh? Doesn't anybody listen if your nice and pleasant?