But the kid wasn't blind... just a dumb@ss!
I've known a couple sight impaired (1 from birth, 1 from accident) folk over the years, and their hearing had adapted HIGHLY. Both of them could tell what kind of pants you were wearing based on the sound made from your legs "swishing" together, what you were drinking based on the sound of the fizz (or lack of), or tell from the clanking that the nextdoor neighbor was drying bluejeans w/ rivots & metal buttons! :O
Hybrids/full electric DO make plenty of noise. While not the same as a dump truck or Yugo, there's still the sound of tires contacting the road and motor/tranny whine... either of the folks above could have heard it coming a mile away "Radar style" if not masked by louder noise!
My point is that putting "noise makers" on quieter vehicles is ridiculous! If their loud enough to be heard over a truck, their loud enough to be obnoxious to everyone else...