The scientific reason is that the 350 watt drum connected to the dryer motor vibrates at 55 hertz which stimulates the female solar plexus. This creates a chain reaction and urges males to assert dominance and proceed with a mating ritual. When you combine this with the enticingly large sums of cash at a typical laundromat, you can see this is a devastating combination. The scantily clad hot body people is a side effect, not the cause.