A lot of burning of unwanted vegetation goes on in the countryside, here in Australia, and probably around the world.
Heaven forbid the vegetation should be left to provide habitat for animals and insects, to enrichen and help structure the soil, and to generally improve the local environment!
I guess it's just too "untidy" for the anally retentive minds of the property owners to handle. Everything must look like a lifeless 1950's suburban yard. So as a result we get a lifeless, boring environment that is hostile to life and the air full of sickening smoke, just so some tight asses can have a "tidy" property!