Some things i dont get..

Just outside my school, about once a week, the community center fogs the streets to help contain the outbreak of mosquitoes. I'm not sure why, but whenever mosquitoes are around, the Korean people are instantly aware of their presence. There seems to be a fear of them, like others might fear killer bees. There are tons of different methods to get rid of the pests, my favorite being the 'electric tennis racket'. This device is exactly as it sounds: a tennis racket sized frame with an electric mesh that shocks its prey with 1.5 volts of power (it feels like more though..).
Anyways, It always amazes me how the parents just stand by and watch their kids running through the insecticides when they fog here. The sprayers move from doorway to alley way, even to food stalls, spraying their killer gas. I've asked my co-teachers and they swear it's safe, and even endorse the school kids going out to play in it. Being kind of new to this tactic of getting rid of mosquitoes, I'm a little shocked. Do they do this in Canada or the States? And if they do, do kids treat the insecticide like a sprinkler?

I guess it's just another one of those things that I don't get, and probably wont get.