I don't buy it, and I'm both a motorcycle rider and a driver.
Some people like loud exhaust, period. It's a cool sound. It makes you feel powerful. Safety aspect is a rationalization for others and possibly yourself. In busy traffic, to another moving vehicle, sound is neither going to be heard clearly nor will it provide directional or distance cues. If they're interested in safety (or would like to think they are), ask them about their full face helmet, which motorcycle course they're thinking of taking next, and what's their training routine in the spring. Maybe whether they're considering a high visibility outfit instead of black leather.
Some people like loud exhaust, period. It's a cool sound. It makes you feel powerful. Safety aspect is a rationalization for others and possibly yourself. In busy traffic, to another moving vehicle, sound is neither going to be heard clearly nor will it provide directional or distance cues. If they're interested in safety (or would like to think they are), ask them about their full face helmet, which motorcycle course they're thinking of taking next, and what's their training routine in the spring. Maybe whether they're considering a high visibility outfit instead of black leather.